Schneider plays Marvin Mange, a man who is critically injured but unknown to him he is put back together by a mad scientist who transplants animal parts, resulting in strange permanent changes to his behavior.
Marvin Mange (Rob Schneider) is an awkward, clumsy nice-guy who dreams of being a police officer like his dad was. He continuously attempts to pass the physical test to become a full-fledged police officer, but despite his repeated attempts, he is unable finish the obstacle course. Marvin gets constantly mistreated by heartless and sleazy Sgt. Sisk (John C. McGinley). He works in the police station as an evidence clerk.
One day, while alone at the station, he receives a robbery call. With no other officers responding to the call, he attempts to take it himself, but ends up driving off the road, tumbling down a mountain and seriously injuring himself. When the car finally comes to a stop, he passes out.
Days later, Marvin returns to his normal life with no memory of what had happened. Suddenly, he's full of life. He can outrun horses, mean dogs are now scared of him, and he does not need his asthma medicine. He thinks it is due to his late-night TV purchase of "Badger Milk", which is guaranteed in the ads to make him stronger.
One day at the park, Marvin meets Rianna (Colleen Haskell) while she's out walking dogs. His animal-like tendencies are slowly taking him over. When a frisbee is thrown in his direction, he cannot control himself, and he jumps to catch it in his mouth.
He goes to the airport to talk to his friend, Miles the security guard (Guy Torry) about his problem. While there, Marvin sniffs out a man trying to hide heroin in his rectum. For uncovering a drug smuggler, Marvin is declared a hero and is made a full-fledged police officer.
As days go by, Marvin's animal instincts are becoming stronger. He often wakes up in strange places, and subsequently, hears about animal attacks that occurred in the middle of the night. Because of these attacks, Dr. Wilder believes that Marvin is out of control. The mad scientist confronts him, takes him to his laboratory, and explains about the grafts and transplants that saved and changed Marvin's life, and gave him remarkable animal powers with certain problem side effects.
Later at a party thrown by the Mayor (Scott Wilson) Marvin chases after a cat and destroys everything around him and is fired on the spot. During his reprimand, he hears something, jumps into the nearby lake and rescues the mayor's son using powers derived from a sea lion and a dolphin. He is swiftly reinstated.
Chief Wilson (Ed Asner) questions Marvin about the late-night attacks on farm animals, because one of witnesses made a police sketch—and it looks like Marvin.
Rianna goes to Marvin's house, where he has barricaded himself inside. They spend the night together, but Marvin wants to be tied up so he cannot hurt anyone anymore. In the morning, he finds himself untied, courtesy of Rianna. Suddenly, the police show up outside. Another attack had happened that night, and the police have come for Marvin. Rianna convinces him to run.
Marvin escapes to the woods, where a huge chase ensues; the police have organized an angry mob as a search party to capture Marvin. While running through the woods, Marvin finds Dr. Wilder. The scientist tells him that there was another "patient" of his that is out of control, and he is in the woods looking for it.
Sergeant Sisk confronts Marvin, and is about to shoot him. Suddenly, the other "animal" jumps from a tree and attacks Sisk. The beast is Rianna. Now, the crowd finds them both together but Miles is there, and takes the blame for everything. He has been claiming that there is reverse discrimination with him since he's black, and that no one wants to hold him accountable for anything. Sure enough, once the mob thinks a black man was responsible, they don't care anymore, and leave.
Marvin and Rianna get married, and have a litter of children that each look like Marvin. While watching television, they see Dr. Wilder win the Nobel Prize. He says he owes it all to his fiancée, who is the same woman from the Badger Milk commercial. When she turns around to kiss him, there are large scars shown on her back, implying that Wilder performed the experiment on her as well.Rob Schneider as Marvin Mange
Colleen Haskell as Rianna Hummingbird Holmes
John C. McGinley as Sgt. Doug Sisk
Guy Torry as Miles
Ed Asner as Chief Wilson
Michael Caton as Dr. Wilder
Louis Lombardi as Fatty
Norm Macdonald as Mob Member
John Farley as Other Mob
Adam Sandler as Townie
Sebastian Jude as the Lost Boy
Charlie Stewart as the Evidence Room Kid #1
Philip Daniel Bolden as the Evidence Room Kid #2
Wes Takahashi, former animator and visual effects supervisor for Industrial Light & Magic, makes a cameo appearance as a news reporter.
The Animal debuted on June 1, 2001, grossing $19.6 million U.S. in its opening weekend. With a production budget of $47 million, the movie grossed $84,772,742 internationally.
This film received negative reviews. Rotten Tomatoes gave the film a score of 30% based on 82 reviews. Metacritic gave the film a score of 43% indicating mixed or average reviews. Rob Schneider was nominated for a Razzie Award for Worst Actor of the Decade for his performance in the film.
Despite receiving mostly negative critical reaction, one supporter of the film at the time of its release was film critic David Manning who gave the film critical praise. In late 2001, Manning was revealed to be a fictitious character created by Sony to fake publicity for the film. At the time, Sony claimed that the error was due to a layout artist who entered 'dummy text' into print advertisements during their design, which was accidentally never replaced with real text.