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A neuralyzer, sometimes spelled as neuralizer, is a device seen in the Men in Black franchise. It is one of the signature tools and considered standard issue employed by the Men in Black. It is a device about the size of an average pen that gives a bright flash which erases the memories of the past hours, days, weeks, months or years, depending on the chosen settings. It first appeared in the first issue of the comic book series, and has appeared in all three films, as well as the animated TV series. It also has changed from red to blue.
In the comic books
The device in the comic books was referred to as a 'neurolyser'. This is also where the concept of using Ray-Ban sunglasses was introduced. It is seen more in the shape of a flashlight than a pen-like shape made popular by the films. It does not simply erase memory like the movie counterpart does, but is a device used for manipulation and control. When neurolysed, a witness is simply hypnotized and does what ever Agent K or J wants them to do, such as provide information, believe a lie and/or pass that lie along as fact.
In the films
A neuralyzer wipes the memory of a target or witness, putting them under a hypnotic state and making them susceptible to suggestion and implantation of false memories. It is used by MIB as a moral substitute to witness elimination by murder, while keeping both the agency's existence and the presence of aliens on Earth unknown to the public. The length of memory erased can be changed using buttons and dials. There are different neuralyzer models with different button and dial configurations, which allow the setting of time spans ranging from minutes to years. The device produces a bright, noisy flash similar to that of a camera.
To avoid the device's effects, agents wear Ray-Ban sunglasses with deeply tinted black lenses that filter out the rays. After using the neuralyzer, the agents have a short period of time to supply new memories to replace the ones they have just erased. If there are more witnesses to neuralyze, or if they are pressed for time, a special team is sent in to supply memories. The neuralyzer cannot delete a specific memory; it can only erase all memories formed during the chosen time span up to the moment of its use.
After being neuralyzed, the witnesses forget the events that are meant to be removed from their memory. However, they can sometimes experience déjà vu if they encounter something closely associated with the erased memories. Agent J (Will Smith) and Dr. Laurel Weaver (Linda Fiorentino) both experience this feeling when they meet in the city morgue; the two had previously met at a police station prior to J's joining MIB, but Agent K had wiped both their memories of the encounter at different times. Agents who retire, resign, or are fired from MIB are neuralyzed, as are rejected agent candidates and trainees.
Changes to the neuralyzer have been featured in the films. In the first movie, the color of its eye was red. This was later changed to blue in the second film. It remains blue in the third film, although the shade is more of a turquoise rather than the previous film's aqua, and the design of the neuralyzer itself is considerably different compared to the previous films. In the first movie, Agent J calls the neuralyzer the "flashy thing"; he disapproves of K's liberal use of it and believes that they should supply the victims with pleasant memories rather than mundane or depressing ones. At the end of the film, J neuralyzes K so he can retire from MIB, wiping out 35 years of his memory.
In the second movie, J acquires a reputation for neuralyzing multiple partners and throwing them out of MIB. He attempts to justify his use of the device on Agent T, citing T's emotional breakdown in a public place, and on Agent L (formerly Laurel Weaver), saying that she wanted to resume her work as a medical examiner. The MIB have also installed neuralyzers in many places, such as Agent J's car and The Statue of Liberty, which has one installed in its torch that is powerful enough to wipe the memories of everyone in the greater New York and New Jersey area.
In the third film the original neuralyzer is seen. It is a large contraption that requires strapping the subject into a platform that is then inserted inside the neuralyzer. Later, the young Agent K (Josh Brolin) is seen with an early portable neuralyzer attached to a battery pack that is clipped to his belt. He used it on young James Darrell Edwards III, saying his father was a hero.
A deneuralyzer is a special chamber room that serves to reverse the effects of a neuralyzer. While the neuralyzer is a small object and works in a single flash, deleting memory within seconds, it takes a huge room for a deneuralyzer and the memory scan lasts for around 5–10 minutes, depending on the memory needed to be recovered. The deneuralyzer is a chamber with a single seat, a huge computer and metal fittings put on a person's head to recover the memory.
The deneuralyzer was only seen and mentioned in the second film, and it was stated that the only "official" deneuralyzer is owned by the MiB. It was designed as a huge toilet bowl, in which J had to reverse the neuralyzer effects on K. However, when the MiB HQ was breached, an emergency protocol filled the room with water and flushed it like a toilet, sending the two agents out to Times Square.
Jack Jeebs, an alien pawn shop owner, owned a second, illegal deneuralyzer in his basement. Unlike the highly sophisticated MiB deneuralyzer, his was built in a Rube Goldberg machine-like style out of primitive tools (bowling ball, old industrial fan, barber chair and a whipped cream mixer), and was controlled by a small computer placed next to it using software Jeebs developed. It was also highly unreliable: Jeebs powered the machine using a boat engine, and the barber chair was loose, shaking K and sending him flying across the room after the process. The machine also malfunctioned and caused a blackout in the entire New York area for a few seconds, but it was up and running again soon after. However, the deneuralyzer was a success, although it took K some time to regain some memories. Jeebs never used it to return memories to other beings, only using the exhaust once to "make some hot-air popcorn". The deneuralyzer took a minute to complete its job. According to Jeebs, his deneuralyzer cannot be used if one is wearing any jewelry or/and is allergic to shellfish. He took the plans for the machine off the internet (where he also advertised the deneuralyzer) and said that he would bring K's memory back in an instant if he had the more advanced MiB software instead of his own.
The neuralyzer has gained popularity outside the franchise. Sundance Channel ranked it No. 4 on its list of "Top 10 Film Inventions We Wish Were Real," saying that the silver pen-looking thing with the red light needs to exist in real life. Top10Kid.com ranked it at No. 7, saying "The uses of eliminating someone’s memories are endless, especially if you are prone to screwing up a lot." MSN puts it "The greatest fictional inventions of all time."
The neuralyzer also appeared in a special segment of How Stuff Works: Sci-Fi Saved My Life dedicated to the MiB franchise. Multiple remakes of it are available in the Android Market complete with sounds and a flash.
In popular culture
In The Simpsons episode "The Fool Monty," when Smithers leaves Vice President Dick Cheney's employment to return to working for Mr. Burns, Cheney zaps him with a neuralyzer. It appeared again in The Simpsons comic No. 178 entitled "The Thingama-Bob from Outer Space," in which Sideshow Bob is taken away by a man wearing a black suit and sunglasses who promises him that he won't remember anything of what has just happened. It also appeared in the Family Guy episode entitled "From Method to Madness," in which Lois Griffin uses it on Chris when he cannot stop saying "boobies" after meeting a family of nudists. It appeared again in "Leggo My Meg-O", where Stewie uses it to erase Meg's memories after killing her apparent kidnapper and boyfriend. In the video game Marvel Heroes, the Neuralyzer appears as an item that resets story progress, referencing the device's ability to make one forget. The item description says "a gift from some friends out of town"