Five teenagers, Roger, Max, Caruso, Fiona and Buzz, gain the power to turn into dinosaurs by getting covered in ooze that mutated their DNA on a school field trip to the tide pools. With the help of their mysterious science teacher, Ms. Moynihan (who is an anthropomorphic velociraptor), they learn to use their unique abilities to protect the planet from Victor Veloci. Victor is widely known as the head of company Raptor Dyne, but is also a 65-million-year-old anthropomorphic velociraptor. His secret identity is unknown to everyone except himself and the audience. His true plan is to turn everyone into dinosaurs and increase the climate to that of the Mesozoic era with the goal of returning the world to how it was when dinosaurs ruled. However, his plans always backfired and thus the return to the age of the dinosaurs was never meant to be. Dino Squad is set in Kittery Point, Maine. Season 2 episodes began airing online on August 4, 2008 before airing on CBS on September 13, 2008.
Ms. Moynihan (Joanne Moynihan) - A science teacher who is a Velociraptor that survived extinction and gained a human form. She can communicate telepathically with the teens.
Max (Rolf Maxwell) - A hunky 18-year-old high school senior in Ms. Moynihan's class. He is the team leader and captain of the football team. His Dino form is a Tyrannosaurus. Max is voiced by Ian Eli Lee.
Caruso (Erwin Caruso) - A handsome high school senior in Ms. Moynihan's class. He is vain and obsessed with the idea of fame, as well as his "good looks". He can be a pain sometimes though as his selfishness and arrogance hurt the team. Though he did prove himself worthy to the squad in episode 23. In that same episode he is revealed to have created his own line of moisturizers. He also practices yoga. His Dino form is a Stegosaurus (although his dino form has five tail spikes, teeth and no beak, unlike the real Stegosaurus). Caruso is voiced by Benjamin Beck.
Fiona (Fiona Flagstaff) - Another high school senior in Ms. Moynihan's class. She is the only girl on the Squad (with the exception of Ms. Moynihan), and has a penchant for fast things like rollerblades or race cars. Ironically what grosses out Fiona entices Buzz (spiders, insects, etc.). She is allergic to spider bites, as revealed in "Never Judge a Dinosaur by its cover". Fiona is the squad's resident mechanic and gear head, and is also a tomboy. Max and Buzz may have a crush on her, but she doesn't seem to notice. Her Dino form is a Spinosaurus. Fiona has a little sister called Terri. Fiona is voiced by Dana Donlan.
Roger (Roger Blair) - Another high school senior in Ms. Moynihan's class. He is very smart and has a prankster streak. He is able to come up with gadgets even though his creations sometimes fail. Is somewhat arrogant like Caruso but helps the team when duty calls. He has a little brother named Mikey. His Dino form is a Styracosaurus (although his dino form has the horn arrangement of a Triceratops). Roger is voiced by Kelcey Watson.
Buzz (Neil Buzmati) - Another high school senior in Ms. Moynihan's class. He is 17 going on 18. His name is same as buzz the mascot and is the youngest member. He's the "punk" kid, who is scared of his own shadow. Several times throughout the series, he also shows affection for small creatures traditionally considered "gross" in European culture, such as rats, snakes, cockroaches, and spiders. Buzz is anything but a coward when he is needed in action. His alternate form, a Pteranodon, is one of the two non-dinosaurs in the Dino Squad.
Rump - The Dino Squad's mischievous pet bull terrier dog. He can transform himself into a strange animal that looks like a hybrid between a pig and a horse. The Dino Squad has not yet determined the species of dinosaur his "dino form" is supposed to be (although since Ms. Moynihan never "taught" him how to control his transformations as she did the kids, it's likely his dino form is mostly canine and it bears a resemblance to an Andrewsarchus). Rump usually gives Caruso a hard time from when he took his jacket in "The Beginning" as a stray dog, up until the episode "Runaway Ugly" when he ate Caruso's cupcake.
Terri - Fiona's brainy little sister. At first she is jealous of Fiona. She appears in 3 episodes (A Mole Lotta Trouble, Wannabe, and Never Judge a Dinosaur by its Cover). Although she may be as intellectual as Roger, she has also exercised substandard judgment—Terri is voiced by Sarah Heinke.
Victor Veloci - The main antagonist and a business magnate who owns Raptor Dyne. He wants to revert Earth back to the way it was millions of years ago in order to facilitate the return of dinosaurs as the dominant species on the planet. His dino form is a Velociraptor. He and Ms. Moynihan were the only survivors of the asteroid that wiped out the dinosaurs.
Henchman - There are many henchmen who work for Raptor Dyne. They wear helmets with faceplates as part of their uniform. In episode 23, Caruso dresses up as one to fake out Veloci's real henchmen.