Teenage Mutant Ninja Turtles II: The Secret of the Ooze is a 1991 American live-action film, based on the Teenage Mutant Ninja Turtle characters. It is the sequel to the 1990 film, Teenage Mutant Ninja Turtles. The Secret of the Ooze was then followed by a third film in 1993, and a fourth film (TMNT) in 2007. The film is commonly abbreviated as TMNT II. The movie is distributed by New Line Cinema. Outside the United States, it is internationally distributed by 20th Century Fox.
The film follows the adventures of the four Turtles: Leonardo, Donatello, Michaelangelo, Raphael, and their Master Splinter. Roughly resuming from the events of the last film, the villain, Shredder, returns to take back command of the Foot Clan, and work towards getting revenge on the Turtles. When he learns the secret behind the Turtles' mutation, he becomes more dangerous than ever. The film sheds some light on the origins of Splinter and the Turtles, as well as introduces two new villains: Tokka and Rahzar.
Unlike the first film, this one rarely showed the use of the Turtles' weapons. They instead fight bare-fisted for much of the film as part of an attempt to tone down the violence of the previous movie. The film was released on March 22, 1991, and received mixed reviews from critics. It departed from much of the darker tone of the 1990 film, and was more light-hearted. The film was successful, and it became the 13th highest grossing film domestically in the year of its release.
Following the Shredder's defeat at the hands of the Teenage Mutant Ninja Turtles, the four live with their news reporter friend April O'Neil while they look for a new home, afraid the Foot will attack them if they return to the sewer. On a night out they encounter a pizza delivery boy named Keno fighting a band of robbers and intervene on his behalf. Meanwhile, the Foot Clan have retreated to a large junkyard, where the Shredder's second-in-command Tatsu declares himself their leader. However, he relinquishes command when the Shredder returns, having survived his encounter with the Turtles and Splinter and now desiring revenge. April interviews Professor Jordan Perry, head scientist of an industrial organization called Techno Global Research Industries (TGRI), on their efforts to neutralize pollutants that have resulted from their experiments. A member of April's camera crew that is a spy for the Foot discovers that toxic waste produced by the company has caused a mutation in nearby dandelion plants, producing exponential growth. Splinter, seeing the report on television, shows the Turtles and April the canister of the "ooze" that caused their mutation, revealing it was manufactured by TGRI.
The Shredder dispatches the Foot to obtain some of the ooze that caused the mutation. The Turtles infiltrate the TGRI laboratory seeking answers, but discover the Foot have kidnapped Perry, and after a skirmish the Foot escapes with the last canister of the ooze. The Shredder forces Perry to expose an alligator snapping turtle and a wolf to the ooze, transforming them into Tokka and Rahzar. Though the Shredder is irritated when they act as infants and consider him their "mother," due to Perry secretly modifying the ooze, but the warlord is impressed with their immense strength and sends them to attack the city. Meanwhile Keno and Raphael infiltrate the Foot by having Keno pose as a new recruit, and the other three Turtles discover a new lair in an abandoned subway station. With Keno's assistance, Raph successfully infiltrates the Foot headquarters, but is captured by the Shredder. Keno escapes to inform the others, but the group is led into a trap and are pitted against Tokka and Rahzar. The Turtles are overwhelmed by their brute strength, but manage to escape into a manhole that the larger mutants cannot fit through, successfully rescuing Perry in the process. Talking with Perry, Donatello is depressed to learn that the ooze was created in a lab accident rather than anything else, but Splinter assures him that he cannot judge his worth based on his origins. Upon learning that the Shredder intends to release Tokka and Rahzar into populated areas unless the Turtles confront them, Perry develops an antidote to counteract the ooze's effects and transform them back into normal animals.
The Turtles meet with the Foot and successfully administer some portion of the anti-mutagen to Tokka and Rahzar by concealing it in donuts, but are discovered and another fight ensues. The fight spills into a nightclub, where the club's singer Vanilla Ice improvises a rap song to prevent a panic by creating the impression that the fight is part of his act. With advice from Perry the Turtles spray fire extinguishers into Tokka and Rahaar's mouths, the carbon dioxide speeding up the anti-mutagen and reverting the two monsters back to their natural forms. After the Turtles take care of the Foot and Tatsu, the Shredder arrives and takes a woman hostage, revealing he still possesses the ooze. Keno arrives and kicks the canister out of his hands, which is recovered by Perry, but the Shredder retains a small vial of the ooze. Using a sound amplifier to magnify a Keytar, the Shredder is blasted through a wall onto the docks outside. The Turtles follow and find that he has used the ooze on himself and mutated into a "Super-Shredder," having consumed the vial of ooze. The Shredder then begins to tear at the dock's support beams. Leonardo tries to reason with the Shredder saying if he collapses the supports, he will die too. The mutated villain does not care and continues to tear at the supports. The Shredder overpowers the Turtles, but his rampant destruction of the dock's supports causes it collapse on top of them, crushing him while the Turtles dive to safety in the water. The Turtles return to their lair triumphant, but are confronted by Splinter with a newspaper showing a picture of them fighting at the club on the front page. As punishment, the Turtles are forced to do flips, Splinter quoting Vanilla Ice's rap and laughing as they begin, proudly saying "I made another funny!".