The Big Bang Theory

This article is about the television series. For the scientific theory, see Big Bang. For other uses, see Big Bang Theory (disambiguation).

"TBBT" redirects here. For the Discovery Channel series, see The Big Brain Theory.

The Big Bang Theory
File:BigBangTheoryTitleCard.png
Genre	Sitcom
Created by	Chuck Lorre Bill Prady
Directed by	Mark Cendrowski
Starring	Johnny Galecki Jim Parsons Kaley Cuoco Simon Helberg Kunal Nayyar Sara Gilbert Melissa Rauch Mayim Bialik Kevin Sussman
Theme music composer	Barenaked Ladies
Opening theme	"Big Bang Theory Theme"
Country of origin	United States
Original language	English
No. of seasons	9
No. of episodes	185 (list of episodes)
Production
Executive producers	Chuck Lorre Steven Molaro Bill Prady
Producer	Faye Oshima Belyeu
Editor	Peter Chakos
Camera setup	Multi-camera
Running time	18–24 minutes (without commercials)
Production companies	Chuck Lorre Productions Warner Bros. Television
Original release
Network	CBS
Release	September 24, 2007 (2007-09-24) – present

The Big Bang Theory (also abbreviated as TBBT) is an American sitcom created by Chuck Lorre and Bill Prady, both of whom serve as executive producers on the show along with Steven Molaro. All three also serve as head writers. The show premiered on CBS on September 24, 2007. The ninth season premiered on September 21, 2015.

The show is primarily centered on five characters living in Pasadena, California: Leonard Hofstadter and Sheldon Cooper, both physicists at Caltech, who share an apartment; Penny, a waitress and aspiring actress who later becomes a pharmaceutical representative, and who lives across the hall; and Leonard and Sheldon's similarly geeky and socially awkward friends and co-workers, aerospace engineer Howard Wolowitz and astrophysicist Raj Koothrappali. Geekiness and intellect of the four guys is contrasted for comic effect with Penny's social skills and common sense.

Over time, supporting characters have been promoted to starring roles: Bernadette Rostenkowski, Howard's girlfriend (later his wife), a microbiologist and former part-time waitress alongside Penny; neuroscientist Amy Farrah Fowler, who joins the group after being matched to Sheldon on a dating website (and later becomes Sheldon's girlfriend); and Stuart Bloom, the cash-strapped owner of the comic book store the characters often visit, who, in season 8, moves in with Howard's mother.

Production

The show's initial pilot, developed for the 2006–07 television season, was substantially different from its current form. The only characters from the initial pilot that were kept for the reshot pilot for the series were Leonard and Sheldon (portrayed by Johnny Galecki and Jim Parsons, respectively, and named after Sheldon Leonard). Althea (Vernee Watson), a character featured in the first episode, was also featured in the initial pilot and brought to the reshot pilot. The cast was rounded off by two female leads: Canadian actress Amanda Walsh as Katie, "a street-hardened, tough-as-nails woman with a vulnerable interior" whom the boys meet after she breaks up with her boyfriend and invite to live in their apartment (Katie was replaced by Penny, portrayed by Kaley Cuoco, in the second pilot); and Iris Bahr as Gilda, a scientist colleague and friend of the boys who was threatened by Katie's presence. The initial pilot used Thomas Dolby's hit "She Blinded Me with Science" as theme music. The test audiences reacted negatively to Katie, but they liked Sheldon and Leonard.

The series was not picked up, but the creators were given an opportunity to retool the show and produce a second pilot. They brought in the remaining cast and retooled the show to its final format. The original unaired pilot has never been officially released, but it has circulated on the Internet. On the evolution of the show, Chuck Lorre said, "We did the 'Big Bang Pilot' about two and a half years ago, and it sucked... but there were two remarkable things that worked perfectly, and that was Johnny and Jim. We rewrote the thing entirely, and then we were blessed with Kaley and Simon and Kunal." As to whether the world will ever see that original pilot, maybe on a future DVD release, Lorre said, "Wow, that would be something, we will see. Show your failures..."

The first and second pilots of The Big Bang Theory were directed by James Burrows, who did not continue with the show. The reworked second pilot led to a 13-episode order by CBS on May 14, 2007. Prior to its airing on CBS, the pilot episode was distributed on iTunes free of charge. The show premiered on September 24, 2007, and was picked up for a full 22-episode season on October 19, 2007. The show is filmed in front of a live audience, and is produced by Warner Bros. Television and Chuck Lorre Productions. Production was halted on November 6, 2007, due to the Writers Guild of America strike. Nearly three months later, on February 4, 2008, the series was temporarily replaced by a short-lived sitcom, Welcome to the Captain. The series returned on March 17, 2008 in an earlier time slot and ultimately only 17 episodes were produced for the first season. After the strike ended, the show was picked up for a second season airing in the 2008–2009 season, premiering in the same time slot on September 22, 2008. With increasing ratings, the show received a two-year renewal through the 2010–11 season in 2009. In 2011, the show was picked up for three more seasons. In March 2014, the show was renewed again for three more years through the 2016–17 season. Therefore the series will at least reach 10 Seasons. This marks the second time the series has gained a three-year renewal.

David Saltzberg, a professor of physics and astronomy at the University of California, Los Angeles, checks scripts and provides dialogue, mathematics equations, and diagrams used as props. According to executive producer/co-creator Bill Prady, "We're working on giving Sheldon an actual problem that he's going to be working on throughout the [first] season so there's actual progress to the boards ... We worked hard to get all the science right."

Several of the actors in The Big Bang Theory previously worked together on Roseanne including Johnny Galecki, Sara Gilbert, Laurie Metcalf (who plays Sheldon's mother, Mary Cooper) and Meagen Fay (who plays Bernadette's mother). Additionally, Lorre was a writer on the series for several seasons.

Theme song

File:BNL BigBang.jpg

Single cover for "Big Bang Theory Theme" by Barenaked Ladies (2007)

The Canadian alternative rock band Barenaked Ladies wrote and recorded the show's theme song, which describes the history and formation of the universe and the Earth. Ed Robertson, co-lead singer and lead guitarist in the band, was asked by Lorre and Prady to write a theme song for the show after the producers attended one of the band's concerts in Los Angeles. By coincidence, Robertson had recently read Simon Singh's book Big Bang, and at the concert, he improvised a freestyle rap about the origins of the universe. Lorre and Prady phoned Robertson shortly thereafter and asked him to write the theme song. Having been asked to write songs for other films and shows only to have them rejected in favor of other artists' songs, Robertson agreed to write the theme only after learning that Lorre and Prady had not asked anyone else.

On October 9, 2007, a full-length (1 minute and 45 seconds) version of the song was released commercially. Although some sources identify the song title as "History of Everything", the cover art for the single identifies the title as Big Bang Theory Theme. A music video was also released via special features on The Complete Fourth Season DVD and Blu-ray set. The theme was included on the band's greatest hits album, Hits from Yesterday & the Day Before, which was released on September 27, 2011. In September 2015, TMZ uncovered court documents showing that Steven Page sued former bandmate Robertson over the song, alleging that he was promised 20% of the proceeds but that Robertson has kept that money entirely for himself.

Actors' salaries

For the first three seasons, Galecki, Parsons, and Cuoco, the three main stars of the show, received at most $60,000 per episode. The salary for the three went up to $200,000 per episode for the fourth season. Their per-episode pay went up an additional $50,000 in each of the following three seasons, culminating in $350,000 per episode in the seventh season. By season seven, the three were also receiving 0.25 point of the series' backend money. Before production began on the eighth season, the five main stars looked to renegotiate new contracts, with Galecki, Parsons, and Cuoco seeking around $1 million per episode, as well as more backend money. Contracts were signed at the beginning of August 2014, giving the three principal actors an estimated $1 million per episode for three years, with the possibility to extend for a fourth year. The deals also include larger pieces of the show, signing bonuses, production deals and advances towards the back-end.

In September 2013, Bialik and Rauch renegotiated the contracts they held since they were introduced to the series in 2010. On their old contracts, each was making $20,000–$30,000 per episode, while the new contracts doubled that, beginning at $60,000 per episode, increasing steadily to $100,000 per episode by the end of the contract, as well as adding another year for both.

In August 2014, Helberg and Nayyar renegotiated their contracts, giving them a per-episode pay in the "mid six-figure range", up from around $100,000 per episode they each received in years prior. The duo, who were looking to have salary parity with Parsons, Galecki and Cuoco, signed their contracts after the studio and producers threatened to write the characters out of the series if a deal could not be reached before the start of production on season 8.

Main cast

Main article: List of The Big Bang Theory characters

File:The Big Bang Theory Cast.jpg

Main characters in The Big Bang Theory. First row from left: Raj Koothrappali, Leonard Hofstadter, Penny, Sheldon Cooper, and Howard Wolowitz. Second row from left: Bernadette Rostenkowski-Wolowitz and Amy Farrah Fowler.

These actors are credited in all episodes of the series:

• Johnny Galecki as Leonard Hofstadter, PhD – An experimental physicist with an IQ of 173, he received his PhD when he was 24 years old. His mother, Dr. Beverly Hofstadter (Christine Baranski), is a neuroscientist and psychiatrist who provided little, if any, nurturing when Leonard was growing up. Like all of the other major male characters, he is a nerd who loves video games, comic books and Dungeons & Dragons. Leonard is also lactose intolerant. The straight man of the series, he shares an apartment in Pasadena with Sheldon. Leonard is smitten with his neighbor Penny when they first meet. They briefly date at the end of season 1 and the start of season 2 and in season 3, they begin a stable romantic relationship. Leonard also briefly dates Leslie and Dr. Stephanie Barnett (Sara Rue) in season 2, and in season 4, he becomes seriously involved with Raj's sister Priya (Aarti Mann), a successful lawyer, but she eventually returns to India and they break up in season 5 when she admits to cheating on him. In season 5, he and Penny get back together, and at the end of season 7, he proposes and she accepts.
• Jim Parsons as Sheldon Cooper, M.A., M.S, Ph.D., Sc.D., B.S.  – Originally from Galveston, Texas, he was a child prodigy with an eidetic memory who began college at the age of 11 (after completing the fifth grade), started graduate studies at 14, and earned a PhD at 16. A theoretical physicist researching quantum mechanics and string theory, he has two master's degrees, a PhD, and an Sc.D. However, despite his IQ of 187, he finds many routine aspects of social situations and life in general difficult to understand and navigate. His father died when he was 14, and his mother, Mary (Laurie Metcalf) is a devout Christian. He also has a twin sister, Missy (Courtney Henggeler), who later has a baby in season 7. He has a poor grasp of other people's feelings and little or no understanding of nuances, often questioning others if a comment is intended as sarcasm. As a result, he is extremely tactless and acts wildly inappropriately much of the time. He is determined to have his own way, boasts of his superior intelligence and belittles the accomplishments of his friends, making him appear petty and childlike. Sheldon has an extremely ritualized way of living (e.g. sitting in the same spot on the sofa in the apartment or knocking on a door three times, each time saying the name of the person he's addressing) and a compulsion to complete things. He is also wary of germs and dislikes physical contact. Despite all these quirks, in season 4, he begins a relationship with Amy, who eventually becomes his girlfriend during season 5. In season 8, Sheldon tells Amy that he loves her.
• Kaley Cuoco as Penny – An aspiring actress from a town outside of Omaha, Nebraska, Penny lives across the hall from Sheldon and Leonard. She attends casting calls and auditions, but is not very successful. To pay the bills, she is a waitress and occasional bartender at The Cheesecake Factory. Penny quits her job in season 7 and at the start of season 8 becomes a pharmaceutical representative at Bernadette's company after having given up hope of becoming a successful actress; she appreciates the financial independence the new job gives her. Penny attended, but did not graduate from a community college (she goes back to school in season 6), but has far more common sense and social awareness than the other main characters. Penny is also very untidy and frequently drinks alcohol. To date, her surname has not been revealed. She dates Leonard at the end of season 1 and the start of season 2, and in season 3, they begin a stable romantic relationship. At the end of season 7, she accepts Leonard's proposal of marriage (after having proposed to him earlier in the season while intoxicated). Aside from Leonard, Penny has dated various men over the course of the series, which is at times brought up by Sheldon. She briefly dated Stuart in season 2, and in seasons 3 and 4 dated Zack Johnson (Brian Thomas Smith), a handsome and friendly but dim-witted guy, whom she married in Las Vegas (they didn't think weddings in Las Vegas were real). In season 4, Penny, Bernadette and Amy form their own group, where they hang out in each other's apartments or go out together. Penny also has a very close friendship with Sheldon, despite his quirks. Cuoco began being credited as Kaley Cuoco-Sweeting starting with the season 7 episode "The Convention Conundrum", following her marriage to tennis player Ryan Sweeting. At the beginning of Season 9, Leonard and Penny get married.
• Simon Helberg as Howard Joel Wolowitz, M.Eng. – An aerospace engineer, Howard is Jewish (although not religious) and lived with his mother Debbie (Carol Ann Susi) until her death. His father left both of them when he was 11 and has not heard from him since, with the exception of a letter on his eighteenth birthday, which he refused to open. Unlike Sheldon, Leonard and Raj, Howard lacks a PhD, earning him Sheldon's scorn. He defends this by pointing out that he has a master's degree in engineering from the elite MIT and that the apparatus he designs are launched into space, unlike the purely abstract work of his friends. He himself goes into space at the end of season 5, training as an astronaut and serving as a payload specialist on the International Space Station, although he often annoys his friends by constantly talking about space. He has a marked sense of humor, which Leonard and Raj occasionally appreciate. In the early seasons of the show, Howard fancies himself a ladies' man and devises outrageous pick-up lines (mainly with Penny), which have limited success with women. In season 3 he starts dating Bernadette, and although they later break up off-screen, they get back together and later get engaged in season 4 and get married at the end of season 5. In season 6, Howard finally moves out of his mother's house and into Bernadette's apartment. Howard also has a tendency to waste money on ridiculous things and often argues with Bernadette over money due to his oddly low income as an engineer and her high income, resulting in Bernadette often giving Howard allowances.
• Kunal Nayyar as Rajesh Ramayan "Raj" Koothrappali, PhD – From New Delhi, India, he works as a particle astrophysicist at Caltech. His family is very wealthy (Sheldon describes them as "Richie Rich rich"). Over the course of the series he communicates with his parents, Dr. and Mrs. V.M. Koothrappali (Brian George and Alice Amter), via webcam (they later divorce in season 8). He is very shy around women and is unable to talk to them for the first six seasons (except for his mother and his sister), unless he drinks alcohol (or at least thinks he has drunk it) or takes an experimental medication. Unfortunately, the former gives him an outrageous, unpredictable personality, while the latter causes unforeseen side effects. Even so, he often has better luck with women than his overly confident best friend, Howard. Raj also has very feminine tastes and often takes on a stereotypical female role in his close friendship with Howard, but he insists that he is not gay. In season 4, his sister Priya stays with him and becomes Leonard's girlfriend (much to Raj's annoyance). In season 6, Raj meets Lucy (Kate Micucci), who also has social anxiety, and they begin a relationship. However, Lucy ends the relationship, as she feels too pressured when he wants her to meet his friends. Afterwards, a heartbroken Raj finally speaks to Penny without having consumed alcohol and overcomes his selective mutism. In season 7, he begins dating Emily Sweeney (Laura Spencer), a dermatologist, and their relationship later becomes exclusive. Raj also has a Yorkshire Terrier called Cinnamon, and the gang often joke about how unusually close he is with his dog.

These actors were first credited as guest stars and later promoted to main cast:

• Sara Gilbert as Leslie Winkle, PhD (recurring season 1, starring season 2, guest star season 3) – a physicist who works in the same lab as Leonard. In appearance, she is essentially Leonard's female counterpart, wearing black-framed glasses and sweat jackets. She is an enemy of Sheldon's, due to their conflicting scientific theories. Though each considers the other to be intellectually inferior, Leslie is much wittier than Sheldon, regularly calls him "dumbass", and usually bests him in their repartee. Leslie has casual sex with Leonard and later Howard. Gilbert and Galecki played the on-screen couple of Darlene Connor and David Healy in Roseanne. Gilbert was promoted to a main cast member during the second season, but was demoted back to guest star status because producers could not come up with enough material for the character. Gilbert left the series after season 3 to focus her efforts on The Talk, on which she serves as executive producer for CBS.
• Melissa Rauch as Bernadette Rostenkowski-Wolowitz, PhD (recurring season 3, starring since season 4) – a young woman with a very high-pitched voice who is initially a waitress co-worker of Penny's, paying her way through graduate school, studying microbiology. Bernadette is of Polish origin and was raised in a Catholic household. Her father Mike (Casey Sander) is a toughened retired police officer and she has four other siblings. Bernadette is introduced to Howard by Penny as a result of an agreement between Howard and Leonard that if either ever ended up with a hot girlfriend, he would get the girlfriend to introduce the other to "a hot chick". At first, they do not get along, apparently having nothing in common, until they find out that they both have overbearing mothers. During season 3, they date and then break up off-screen. They get back together and get engaged in season 4 and marry at the end of season 5. After successfully defending her doctoral thesis, she lands a high-paying research position at the end of season 4 (her high income becomes a source of conflict between her and Howard in later seasons). Although generally a sweet and good natured person, Bernadette has a very short temper and can be vindictive and lash out when provoked, often sounding like Howard's mother, and intimidating her colleagues. She is also shown to have a competitive streak.
• Mayim Bialik, PhD, as Amy Farrah Fowler, PhD (guest star season 3, starring since mid-season 4) – a woman selected by an online dating site as Sheldon's perfect mate after Raj and Howard secretly set up an account using Sheldon's information, prompting Raj to comment, "We finally have proof that aliens walk among us!" Amy is from Glendale and is a fan of Little House on the Prairie. She and Sheldon initially have many similar traits, though after befriending Penny and Bernadette, Amy eventually becomes more interested in social and romantic interaction and is more socially aware than Sheldon. Once she and Sheldon meet, she becomes, as Sheldon puts it, a girl who is his friend, but not his "girlfriend". Their relationship slowly progresses up to the point where Sheldon considers her his girlfriend and tells her that he loves her. Amy's sexual frustration in her relationship with Sheldon is a recurring topic in the series. Amy also believes she and Penny are best friends ("besties", as she puts it), a sentiment that Penny does not share. Penny eventually becomes a real friend, overlooking Amy's Sheldon-like qualities. Amy's admiration for Penny has at times bordered on physical attraction. Amy has a PhD in neurobiology, and frequently uses monkeys in her research and experiments. Bialik herself has a doctorate in neuroscience.
• Kevin Sussman as Stuart Bloom (recurring seasons 2–5, & 7, starring season 6 & 8) – the mild-mannered, under-confident individual who runs the comic book store that the guys frequent. A brilliant artist, Stuart is a graduate of the prestigious Rhode Island School of Design and though he is socially awkward, he possesses slightly better social skills than the rest of the guys. Unlike the others he is not a techno-geek. During Stuart's first appearance, the guys bring Penny along to the store, and he manages to ask her on a date. They go out a few times, until Penny mistakenly calls him "Leonard" while they are making out, leaving him devastated. In season 4, he implies he is in financial trouble and that the comic book store is now also his home. At Howard's bachelor party, Stuart uses his toast to tell Howard how lucky he is and compares it to his own situation of living in the back of his store. In season 6, he is invited to join the guys' group while Howard is in space. At the end of season 7, the comic book store burns down and he gets a new job caring for Howard's mother. The two become close and develop a strange relationship, much to the annoyance of Howard. He also briefly dates Howard's second cousin Jeanie (Kara Luiz), to whom Howard lost his virginity.

Scientist cameos

See also: List of The Big Bang Theory characters § Notable guest stars appearing as themselves

As the theme of the show revolves around science, many distinguished and high profile scientists have appeared as guest stars on the show. Famous astrophysicist and Nobel laureate George Smoot had a cameo appearance in episode 17 "The Terminator Decoupling", of the second season. Theoretical physicist Brian Greene also appeared on the show in "The Herb Garden Germination", episode 20 of the fourth season. Astrophysicist, science populizer, and physics outreach specialist, Neil deGrasse Tyson appeared in "The Apology Insufficiency", episode 7 of the fourth season. Cosmologist Stephen Hawking made a short guest appearance in the fifth-season episode "The Hawking Excitation" on April 5, 2012. In the episode he meets Sheldon Cooper and points out a mistake in Sheldon's new Higgs boson analysis. Hawking also speaks on the phone at the end of the episode "The Extract Obliteration" with Sheldon, but is not seen on-camera. In season 8 Episode 14, Hawking video-conferences with Sheldon and Leonard after trolling online their joint paper. In the end of season 5 and the beginning of season 6 NASA astronaut Michael J. Massimino was featured as himself multiple times in the role of Howard's fellow astronaut. In season 7 Bill Nye appears in an episode ("The Proton Displacement") in which Sheldon feels slighted by his childhood science-hero, Professor Proton, hiring Bill to fill the void.

Episodes

Main article: List of The Big Bang Theory episodes

Season	Episodes		Originally aired		Viewers rank	U.S. Viewers (millions)	18–49 rank	18–49 rating/share
			First aired	Last aired
1	17		September 24, 2007 (2007-09-24)	May 19, 2008 (2008-05-19)	68	8.34	46	3.3/8
2	23		September 22, 2008 (2008-09-22)	May 11, 2009 (2009-05-11)	40	10.07	—	—
3	23		September 21, 2009 (2009-09-21)	May 24, 2010 (2010-05-24)	12	14.22	5	5.3/13
4	24		September 23, 2010 (2010-09-23)	May 19, 2011 (2011-05-19)	13	13.21	7	4.4/13
5	24		September 22, 2011 (2011-09-22)	May 10, 2012 (2012-05-10)	8	15.82	6	5.5/17
6	24		September 27, 2012 (2012-09-27)	May 16, 2013 (2013-05-16)	3	18.68	2	6.2/19
7	24		September 26, 2013 (2013-09-26)	May 15, 2014 (2014-05-15)	2	19.96	2	6.2/20
8	24		September 22, 2014 (2014-09-22)	May 7, 2015 (2015-05-07)	2	19.05	4	5.6/17
9	24		September 21, 2015 (2015-09-21)	May 12, 2016 (2016-05-12)	2	20.36	3	5.8/19
10	24		September 19, 2016 (2016-09-19)	May 11, 2017 (2017-05-11)	2	18.99	3	4.9/19
11	24		September 25, 2017 (2017-09-25)	May 10, 2018 (2018-05-10)	1	18.63	5	4.4
12	24		September 24, 2018 (2018-09-24)	May 16, 2019 (2019-05-16)	2	17.31	6	3.6

Recurring themes and elements

Science

Much of the show focuses on science, particularly physics. The four main male characters are employed at Caltech and have science-related occupations, as do Bernadette and Amy. The characters frequently banter about scientific theories or news (notably around the start of the show), and make science-related jokes.

Science has also interfered with the characters' romantic lives. Leslie breaks up with Leonard when he sides with Sheldon in his support for string theory rather than loop quantum gravity. When Leonard joins Sheldon, Raj, and Howard on a three-month Arctic research trip, it separates Leonard and Penny at a time their relationship is budding. When Bernadette takes an interest in Leonard's work, it makes both Penny and Howard envious and results in Howard confronting Leonard, and Penny asking Sheldon to teach her physics. Sheldon and Amy also briefly end their relationship after an argument over which of their fields is superior.

David Saltzberg, who has a PhD in physics, has served as the science consultant for the show for six seasons and attends every taping. While Saltzberg knows physics, he sometimes needs assistance from Mayim Bialik, who has a PhD in neuroscience. Saltzberg sees early versions of scripts which need scientific information added to them, and he also points out where the writers, despite their knowledge of science, have made a mistake. He is usually not needed during a taping unless a lot of science, and especially the whiteboard, is involved.

Science fiction, fantasy, comic books and gaming

The four main male characters are all avid science fiction, fantasy, and comic book fans and memorabilia collectors.

Star Trek in particular is frequently referenced and Sheldon identifies strongly with the character of Spock, so much so that when he is given a used napkin signed by Leonard Nimoy as a Christmas gift from Penny he is overwhelmed with excitement and gratitude ("I possess the DNA of Leonard Nimoy?!"). Star Trek: The Original Series cast member George Takei has made a cameo, and Leonard Nimoy made a cameo as the voice of Sheldon's vintage Mr. Spock action figure (both cameos were in dream sequences). Star Trek: The Next Generation cast members Brent Spiner and LeVar Burton have had cameos as themselves, while Wil Wheaton has a recurring role as a fictionalized version of himself.

They are also fans of Star Wars, Battlestar Galactica, and Doctor Who. In the episode "The Ornithophobia Diffusion", when there is a delay in watching Star Wars on Blu-ray, Howard complains, "If we don't start soon, George Lucas is going to change it again" (referring to Lucas' controversial alterations to the films) and in "The Hot Troll Deviation", Katee Sackhoff of Battlestar Galactica appeared as Howard's fantasy dream girl. The characters have different tastes in franchises with Sheldon praising Firefly but disapproving of Leonard's enjoyment of Babylon 5. With regard to fantasy, the four make frequent references to The Lord of the Rings and Harry Potter novels and movies. Additionally, Howard can speak Sindarin, one of the two Elvish languages from The Lord of the Rings.

Wednesday night is the group's designated "comic book night" because that is the day of the week when new comic books are released. The comic book store is run by fellow geek and recurring character Stuart. On a number of occasions, the group members have dressed up as pop culture characters, including The Flash, Aquaman, Frodo Baggins, Superman, Batman, Spock, The Doctor, Green Lantern, and Thor. As a consequence of losing a bet to Stuart and Wil Wheaton, the group members are forced to visit the comic book store dressed as Catwoman, Wonder Woman, Batgirl, and Supergirl. DC Comics announced that, to promote its comics, the company will sponsor Sheldon wearing Green Lantern T-shirts.

Various games have been featured, as well as referenced, on the show (e.g. World of Warcraft, Halo, Mario, etc.), including fictional games like Mystic Warlords of Ka'a (which became a reality in 2011) and Rock-paper-scissors-lizard-Spock.

Leonard and Penny's relationship

One of the recurring plot lines is the relationship between Leonard and Penny. Leonard becomes attracted to Penny in the pilot episode and his need to do favors for her is a frequent point of humor in the first season. Their first long term relationship begins when Leonard returns from a three-month expedition to the North Pole in the season 3 premiere. However, when Leonard tells Penny that he loves her, she realizes she cannot say it back. Both Leonard and Penny go on to date other people; most notably with Leonard dating Raj's sister Priya for much of season 4. This relationship is jeopardized when Leonard comes to falsely believe that Raj has slept with Penny, and ultimately ends when Priya sleeps with a former boyfriend in "The Good Guy Fluctuation".

Penny, who admits to missing Leonard in "The Roommate Transmogrification", accepts his request to renew their relationship in "The Beta Test Initiation". After Penny suggests having sex in "The Launch Acceleration", Leonard breaks the mood by proposing to her. Penny says "no" but does not break up with him. She stops a proposal a second time in "The Tangible Affection Proof". In the sixth season episode, "The 43 Peculiarity", Penny finally tells Leonard that she loves him. Although they both feel jealousy when the other receives significant attention from the opposite sex, Penny is secure enough in their relationship to send him off on an exciting four-month expedition without worrying in "The Bon Voyage Reaction". After Leonard returns, their relationship blossoms over the seventh season. In the penultimate episode "The Gorilla Dissolution", Penny admits that they should marry and when Leonard realizes that she is serious, he proposes with a ring that he had been saving for years.

Sheldon and Amy's relationship

In the third season finale, Raj and Howard search for a woman compatible with Sheldon and discover neurobiologist Amy Farrah Fowler. Like him, she has a history of social ineptitude and participates in online dating only to fulfill an agreement with her mother. This spawns a storyline in which Sheldon and Amy communicate daily while insisting to Leonard and Penny that they are not romantically involved. In "The Agreement Dissection", Sheldon and Amy talk in her apartment after a night of dancing and she kisses him on the lips. Instead of getting annoyed, Sheldon says "fascinating" and later asks Amy to be his girlfriend in "The Flaming Spittoon Acquisition". The same night he draws up "The Relationship Agreement" to verify the ground rules of him as her boyfriend and vice versa (similar to his "Roommate Agreement" with Leonard). Amy agrees but later regrets not having a lawyer read through it.

In the episode "The Launch Acceleration", Amy tries to use her "neurobiology bag of tricks" to increase the attraction between herself and Sheldon. In the final fifth season episode "The Countdown Reflection", Sheldon takes Amy's hand as Howard is launched into space. In the sixth season first episode "The Date Night Variable", after a dinner in which Sheldon fails to live up to this expectation, Amy gives Sheldon an ultimatum that their relationship is over unless he tells her something from his heart. Amy accepts Sheldon's romantic speech even after learning that it is a line from the first Spider-Man movie. In "The Cooper/Kripke Inversion" Sheldon states that he has been working on his discomfort about physical contact and admits that "it's a possibility" that he could one day have sex with Amy. Amy is revealed to have similar feelings in "The Love Spell Potential". Sheldon explains that he never thought about intimacy with anyone before Amy.

"The Locomotive Manipulation" is the first episode in which Sheldon initiates a kiss with Amy. Although initially done in a fit of sarcasm, he discovers that he enjoys the feeling. Consequently, Sheldon slowly starts to open up over the rest of the season, and starts a more intimate relationship with Amy. However, in the season finale, Sheldon leaves temporarily to cope with several changes and Amy becomes distraught. However, in "The Prom Equivalency" hides in his room to avoid going to a mock prom reenactment with her. In the resulting stand-off, Amy is about to confess that she loves Sheldon, but he surprises her by saying that he loves her too. This prompts Amy to have a panic attack.

In the season eight finale, Sheldon and Amy get into a fight about commitment on their 5-year anniversary. Amy tells Sheldon that she needs to think about the future of their relationship. After she leaves, Sheldon reveals privately that he has an engagement ring and is now confused about what to do with it. In the first episode of season nine it is revealed that the ring belonged to Sheldon's grandmother, and strangely, that Sheldon also has an "idiot brother" in addition to the twin sister we know about. 11 hours after Amy said she needed to think about the relationship, Sheldon appears in front of her door, urging her to make up her mind about their relationship's status. After an insult from Sheldon at Howard and Bernadette's place, Amy officially breaks up with him.

Religion

A recurrent theme is Sheldon's conflict with his devout mother, Mary, possessing creationist beliefs referred to by Sheldon as "pre-Enlightenment mythology". Evidence of Sheldon's irreligion is seen when he is heard exclaiming "Why hast thou forsaken me, o deity whose existence I doubt?" upon the discovery that his World of Warcraft account has been hacked. According to Raj, Sheldon also begged the deity in which he did not believe to kill him quickly upon getting food poisoning at the Rose Bowl. On the other hand, Sheldon says he wishes "to employ his rare and precious mental faculties to tear the mask off nature and stare at the face of God." Sheldon's religious upbringing leads to moments of religious interjection when his emotions are high – on one occasion, he happily exclaims "Thank you, Jesus!" when he scores a strike in bowling, quickly adding "As my mother would say." In addition, he frequently says the word "Lord" when he is upset.

At the same time, a running gag in the series is the fact that Howard, who is Jewish and Raj, who is Hindu, frequently defy many of their respective religious customs without worry, such as their constant flouting of dietary prohibitions. They both also tend to give each other grief about them. In the episode "The Financial Permeability", Raj quotes from the book of Leviticus after Howard eats pork, and Howard counters with the fact that he keeps quiet when Raj eats a Whopper. Nevertheless, they are seen to be semi-observant. Raj, for example, occasionally mentions reincarnation and explains his belief in karma, opining that it is "practically Newtonian – for every action there is an equal and opposite reaction." Howard wears fake tattoo sleeves during a failed plan for him and Raj to pick up Goth women so he can complete his quest "and still get buried in a Jewish cemetery"; at another point, Sheldon criticizes him by saying Howard does not join his friends for video game competitions during the Jewish High Holidays.

Another theme is Penny's confidence in supernatural concepts such as ghosts, astrology, psychics, and voodoo that frequently conflict with Leonard and Sheldon's scientific knowledge and skepticism. This is first seen in the Pilot, when she makes reference to her being a Sagittarius but is most frequently seen in an episode in which she and Leonard have a falling out over the validity of psychics.

Howard's mother

In scenes set at Howard's home in which he interacts with his never-seen mother (voiced by Carol Ann Susi until her death), he always does so via shouting conversations between the rooms in his house, and she similarly interacts with other characters in this manner. She reflects the Jewish mother stereotype in some ways, such as being overly controlling of Howard's adult life and sometimes trying to make him feel guilty about causing her trouble. She is dependent on Howard, as she requires him to help her with her wig and makeup in the morning. Howard in turn is attached to his mother to the point where she still cuts his meat for him, takes him to the dentist, does his laundry and "grounds" him when he returns home after briefly moving out. Until Howard's marriage to Bernadette in the fifth season finale, Howard's former living situation led Leonard's psychiatrist mother to speculate that he may suffer from some type of pathology, and Sheldon to refer to their relationship as Oedipal. In season 8, Howard's mother dies in her sleep while in Florida, which devastates Howard and Stuart, who briefly lived with Mrs. Wolowitz.

Vanity cards

Like most shows created by Chuck Lorre, The Big Bang Theory ends by showing a vanity card written by Lorre after the credits, followed by the Warner Bros. Television closing logo. These cards are archived on Lorre's website.

The Theorists

Through the use of his vanity cards at the end of episodes, Lorre alleged that the program had been plagiarized by a show produced and aired in Belarus. Officially titled Теоретики (The Theorists), the show features "clones" of the main characters, a similar opening sequence, and what appears to be a very close Russian translation of the scripts. Lorre expressed annoyance and described his inquiry with the Warner Brothers legal department about options. The television production company and station's close relationship with the Belarus government was cited as the reason that any attempt to claim copyright infringement would be in vain because the company copying the episodes is operated by the government.

However, no legal action was required to end production of the other show: as soon as the word got out that the show was unlicensed, the actors quit and the producers cancelled it. Dmitriy Tankovich (who plays Leonard's counterpart, "Seva") said in an interview: "I'm upset. At first, the actors were told all legal issues were resolved. We didn't know it wasn't the case, so when the creators of The Big Bang Theory started talking about the show, I was embarrassed. I can't understand why our people first do, and then think. I consider this to be the rock bottom of my career. And I don't want to take part in a stolen show".

Reception

Critical reception

The Big Bang Theory initially received mixed reviews and originally received a score of 57/100 from review aggregator Metacritic, indicating "mixed or average reviews". Tom Shales of The Washington Post gave the show a positive review, saying "Big Bang is the funniest new sitcom of the season". Robert Bianco of USA Today also gave the show a positive review, saying "This may not be the sitcom breakthrough for which we've all been hoping, but Lorre has produced a first episode that leaves you eager to try the second". Robert Lloyd of the Los Angeles Times gave a mixed review, stating "It's just the same joke endlessly repeated – the everyday translated into geek-speak, and the obscure and difficult treated as if it were common knowledge". Mike Duffy of the Detroit Free Press gave a negative review, stating "This is by far the least charming—the lame, leering sitcom tales of two brainiac losers goofily smitten by the babelicious girl next door. It's about as witty as a pocket protector".

However, it received very positive reviews in later seasons. James Chamberlin of IGN gave season 2 an 8.4 out of 10 score, saying, "This may be a show about nerds, but you don't have to be a brainiac to enjoy it." Amanda Sloane Murray, writing for the same website, gave season three nine out of 10, describing it as "more intelligent than most sitcoms in recent memory". The American Film Institute ranked season three one of the 10 best television seasons of 2009.

Leigh H. Edwards of PopMatters gave season 4 an 8/10, commenting "The comic commentary may be poking gentle fun at nerds, but the real target of the show's sharp satire is the arbitrary, self-serving stupidity of mainstream culture". On the other hand, Brian Tallerico of Hollywood Chicago panned the series writing: "There's nothing here that seems even remotely original."

Tom Gliatto of People remarked of season 5, "It's bright and obvious as a cartoon yet written with a clean, precise patter of jokes. It's also very well cast".

Kate Ward of Entertainment Weekly gave season 6 a 91/100, remarking "Bialik manages to steal scenes from Parsons as if she's been with the crew since, well, the big bang". Robert Bianco continued to give a positive review, noting "When it comes to making viewers catch their breath from laughing, no show tops Big Bang, and that's an ability that should never be undervalued in a comedy. Bang is one of those rare series where just thinking about some of the plots is enough to make you laugh all over again". On the other hand, June Thomas of Slant Magazine gave the season a negative review, calling it "disappointing".

U.S. standard ratings

The Big Bang Theory started off slowly in the ratings, failing to make the top 50 in its first season (ranking 68th), and ranking 44th in its second season. When the third season premiered on September 21, 2009, however, The Big Bang Theory ranked as CBS's highest-rated show of that evening in the adults 18–49 demographic (4.6/10) along with a then-series-high 12.83 million viewers. After the first three seasons aired at different times on Monday nights, CBS moved the show to Thursdays at 8:00 ET for the 2010–2011 schedule, to be in direct competition with NBC's Comedy Block and Fox's American Idol (then the longest reigning leading primetime show on U.S. television from 2004 to 2011). During its fourth season, it became television's highest rated comedy, just barely beating out eight-year champ Two and a Half Men. However, in the age 18–49 demographic (the show's target age range), it was the second highest rated comedy, behind ABC's Modern Family. The fifth season opened with viewing figures of over 14 million.

The sixth season boasts some of the highest-rated episodes for the show so far, with a then-new series high set with "The Bakersfield Expedition", with 20 million viewers, a first for the series, which along with NCIS, made CBS the first network to have two scripted series reach that large an audience in the same week since 2007. In the sixth season, the show became the highest rated and viewed scripted show in the 18–49 demographic, trailing only the live regular NBC Sunday Night Football coverage, and was third in total viewers, trailing NCIS and Sunday Night Football. Season seven of the show opened strong, continuing the success gained in season six, with the second episode of the premiere, "The Deception Verification", setting the new series high in viewers with 20.44 million.

Showrunner Steve Molaro, who took over from Bill Prady with the sixth season, credits some of the show's success to the sitcom's exposure in off-network syndication, particularly on TBS, while Michael Schneider of TV Guide attributes it to the timeslot move two seasons earlier. Chuck Lorre and CBS Entertainment president Nina Tassler also credit the success to the influence of Molaro, in particular the deepening exploration of the firmly established regular characters and their interpersonal relationships, such as the on-again, off-again relationship between Leonard and Penny. Throughout much of the 2012–13 season, The Big Bang Theory placed first in all of syndication ratings, receiving formidable competition from only Judge Judy and Wheel of Fortune (first-run syndication programs). By the end of the 2012–13 television season, The Big Bang Theory had dethroned Judge Judy as the ratings leader in all of syndicated programming with 7.1, Judy descending to second place for that season with a 7.0. The Big Bang Theory did not place first in syndication ratings for the 2013–14 television season, beaten out by Judge Judy.

Season	Timeslot (ET)	Season premiere	Season finale	TV season	No. of episodes	Rank	Avg. viewers (in millions)	Most watched episode	Viewers (millions)
1	Monday 8:30 p.m. (September 24 – November 12, 2007) Monday 8:00 p.m. (March 17 – May 19, 2008)	September 24, 2007	May 19, 2008	2007–08	17	68	8.31	"The Dumpling Paradox"	9.68
2	Monday 8:00 p.m. (September 22, 2008 – May 11, 2009) Monday 9:30 p.m. (February 9, 2009)	September 22, 2008	May 11, 2009	2008–09	23	44	10.00	"The Maternal Capacitance"	13.11
3	Monday 9:30 p.m. (September 21, 2009 – May 24, 2010) Monday 9:00 p.m. (May 3, 2010)	September 21, 2009	May 24, 2010	2009–10	23	12	14.14	"The Precious Fragmentation"	16.32
4	Thursday 8:00 p.m.	September 23, 2010	May 19, 2011	2010–11	24	15	13.14	"The Robotic Manipulation"	14.04
5		September 22, 2011	May 10, 2012	2011–12	24	8	15.82	"The Friendship Contraction"	16.54
6		September 27, 2012	May 16, 2013	2012–13	24	3	18.68	"The Bakersfield Expedition"	20.00
7		September 26, 2013	May 15, 2014	2013–14	24	2	19.96	"The Deception Verification"	20.44
8	Monday 8:00 p.m. (September 22, 2014 – October 20, 2014) Thursday 8:00 p.m. (October 30, 2014 – May 7, 2015)	September 22, 2014	May 7, 2015	2014–15	24	2	19.05	"The Junior Professor Solution"	18.30
9	Monday 8:00 p.m. (September 21, 2015 – October 26, 2015) Thursday 8:00 p.m. (November 5, 2015 – )	September 21, 2015	—	2015–16	—	—	—	—	—

UK distribution and ratings

The show made its UK debut on Channel 4 on February 14, 2008. The show was also shown as a 'first-look' on Channel 4's digital offshoot E4 prior to the main channel's airing. While the show's ratings were not deemed strong enough for the main channel, they were considered the opposite for E4. For each following season, all episodes were shown first-run on E4, with episodes only aired on the main channel in a repeat capacity, usually on a weekend morning. From the third season, the show aired in two parts, being split so that it could air new episodes for longer throughout the year. This was due to rising ratings. The first part began airing on December 17, 2009 at 9:00 p.m. while the second part, containing the remaining eleven episodes, began airing in the same time period from May 6, 2010. The first half of the fourth season began airing on November 4, 2010, at 9:00 p.m., drawing 877,000 viewers, with a further 256,000 watching on the E4+1 hour service. This gave the show an overall total of 1.13 million viewers, making it E4's most watched programme for that week. The increased ratings continued over subsequent weeks. The fourth season's second half began on June 30, 2011. Season 5 began airing on November 3, 2011 at 8:00 p.m. as part of E4's Comedy Thursdays, acting as a lead-in to the channel's newest comedy, Perfect Couples. Episode 19, the highest-viewed episode of the season, attracted 1.4 million viewers. Season 6 premiered on November 15, 2012, with 1.89 million viewers and a further 469,000 on the time shift channel, bringing the total to 2.31 million, E4's highest viewing ratings of 2012, and the highest the channel had received since June 2011. The sixth season returned in mid 2013 to finish airing the remaining episodes. Season 7 premiered on E4 on October 31, 2013 at 8:30pm and hit multiple ratings records this season. The second half of season seven aired in mid 2014. The eighth season premiered on E4 on October 23, 2014 at 8:30 p.m. During its eighth season, The Big Bang Theory shared its 8:30 p.m. time period with fellow CBS comedy, 2 Broke Girls. Following the airing of the first eight episodes of that show's fourth season, The Big Bang Theory returned to finish airing its eighth season on March 19, 2015.

Canadian ratings

The Big Bang Theory started off quietly in Canada, but managed to garner major success in later seasons. The Big Bang Theory is telecast throughout Canada via the CTV Television Network in simultaneous substitution with cross-border CBS affiliates. Now immensely popular in Canada, The Big Bang Theory is also rerun daily on the Canadian cable channel The Comedy Network.

The season 4 premiere garnered an estimated 3.1 million viewers across Canada. This is the largest audience for a sitcom since the series finale of Friends. The Big Bang Theory has pulled ahead and has now become the most-watched entertainment television show in Canada.

Broadcast

The Big Bang Theory premiered in the United States on September 24, 2007 on CBS. The series debuted in Canada on CTV in September 2007. On February 14, 2008, the series debuted in the United Kingdom on channels E4 (HD) and Channel 4. In Australia the first seven seasons of the series will begin airing on the Seven Network and 7mate from October 2015.

Syndication

In May 2010, it was reported that the show had been picked up for syndication, mainly among Fox's owned and operated stations and other local stations, with Warner Bros. Television's sister cable network TBS holding the show's cable syndication rights. Broadcast of old shows began airing in September 2011. TBS now airs the series in primetime on Tuesdays, Wednesdays, and Thursdays, with evening broadcasts on Saturdays (TBS's local sister station in Atlanta also holds local weeknight rights to the series). Although details of the syndication deal have not been revealed, it was reported the deal "set a record price for a cable off-network sitcom purchase". CTV holds national broadcast syndication rights in Canada, while sister cable network The Comedy Network holds cable rights.

Online media

Warner Bros. Television controls the online rights for the show. Full episodes are available at tv.com, while short clips and recently aired full episodes are available on cbs.com. In Canada, recent episode(s) and pictures are available on CTV.ca. After the show has aired in New Zealand the shows are available in full online at TVNZ's on demand web service.

DVD/Blu-ray releases

DVD and Blu-ray release dates for The Big Bang Theory

Name	Release dates			No. of episodes	Additional Information
	Region 1	Region 2	Region 4
The Complete First Season	September 2, 2008	January 12, 2009	April 3, 2009	17	The three-disc box set includes all 17 episodes. The one extra feature is an 18-minute short entitled "Quantum Mechanics of The Big Bang Theory: Series Cast and Creators on Why It's Cool to Be a Geek". Running Time: 355 minutes.
The Complete Second Season	September 15, 2009	October 19, 2009	March 3, 2010	23	The four-disc box set includes all 23 episodes. Special features include a gag reel, "Physicist to the Stars: Real-Life Physicist/UCLA professor David Saltzberg's consulting relationship to the Show", and "Testing the Infinite Hilarity Hypothesis in relation to the Big Bang Theory: Season 2's Unique Characters and Characteristics". Running Time: 481 minutes.
The Complete Third Season	September 14, 2010	September 27, 2010	October 13, 2010	23	The three-disc box set includes all 23 episodes. Special features include a set tour with Simon Helberg and Kunal Nayyar, an inside look on the third season and a gag reel. This is the first time a season of the show was released on Blu-ray Disc in a two-disc set, in conjunction with the DVD release. Running Time: 472 minutes.
The Complete Fourth Season	September 13, 2011	September 26, 2011	October 5, 2011	24	The three-disc box set includes all 24 episodes. Special features include the story behind the show's theme song with Barenaked Ladies, along with the music video for the theme song, cast interviews with each other, and a gag reel. Running time: 529 minutes. Also available on Blu-ray as a two-disc set, with an exclusive behind-the-scenes look at the taping of "The Wildebeest Implementation".
The Complete Fifth Season	September 11, 2012	September 3, 2012	October 1, 2012	24	The three-disc box set includes all 24 episodes. Special features include "The Big Bang Theory at 100", a featurette on the show's 100th episode, "The Big Bang Theory's Laws of Reflection", "Professors of Production", and a gag reel. Running time: 552 minutes. Also available on Blu-ray/DVD combo pack with UltraViolet download.
The Complete Sixth Season	September 10, 2013	September 2, 2013	September 18, 2013	24	The three-disc box set contains all 24 episodes. Special features include "The Big Bang Theory: The Final Comedy Frontier", where astronauts Buzz Aldrin and Mike Massimino join the cast to analyze Howard's space mission, "Houston, We Have a Sitcom", "Electromagnetism: The Best Relationship Moments in Season 6", "The Big Bang Theory at Paleyfest 2013", and a gag reel. Running time: 477 minutes. Also available on Blu-ray/DVD combo pack with UltraViolet download.

• Despite the third, fourth, fifth, and sixth seasons receiving Blu-ray releases in conjunction with their DVD releases, the first and second seasons were only available on DVD upon their time of release. Warner Bros. has since released the first two seasons on Blu-ray/DVD combo packs with UltraViolet downloads on July 10, 2012. All of the episodes from seasons 1 & 2 on Blu-ray received newly remastered surround-sound audio, with the first season sporting a never-before-seen gag reel, which was not included during the initial first season DVD release.

Awards and nominations

Main article: List of awards and nominations received by The Big Bang Theory

In August 2009, the sitcom won the best comedy series TCA award and Jim Parsons (Sheldon) won the award for individual achievement in comedy. In 2010, the show won the People's Choice Award for Favorite Comedy, while Parsons won a Primetime Emmy Award for Outstanding Lead Actor in a Comedy Series. On January 16, 2011, Parsons was awarded a Golden Globe for Best Performance by an Actor in a Television Series – Comedy or Musical, an award that was presented by co-star Kaley Cuoco. On September 18, 2011, Parsons was again awarded an Emmy for Best Actor in a Comedy Series. On January 9, 2013, the show won People's Choice Award for Favorite Comedy for a second time. On August 25, 2014, Jim Parsons was awarded an Emmy for Best Actor in a Comedy Series.

Merchandise

On March 16, 2014, a Lego Ideas project portraying the living room scene in Lego form with the whole cast as minifigures reached 10.000 supporters on the platform, which qualified it to be considered as an official set by the Lego Ideas review board. On November 7, 2014, Lego Ideas approved the design and began refining it. The set was released in August 2015, with an exclusive pre-sale taking place at the San Diego Comic-Con International.

External links

• Official website
• Vanity Cards Archive for The Big Bang Theory
• The Big Bang Theory at IMDb
• The Big Bang Theory at Rotten Tomatoes