It’s been a year since the Teenage Ninja Mutant Turtles defeated the evil Shredder (Francois Chau). Currently the turtles and their sensei Splinter are living with April O’Neil (Paige Turco) until they can find a new hideout. Roy’s Pizza is a frequent visitor to her apartment. Keno (Ernie Reyes Jr.) is a pizza delivery boy making another stop at April’s place. In front of her apartment he sees several masked burglars. He follows them but ends up being discovered by the gang. The turtles come to his rescue and defeat the ninja style burglars.

Meanwhile at a junk yard Tatsu (Toshiro Obata) is running the remnants of the foot gang of thieves. Suddenly Shredder appears having managed to survive when everyone thought he perished.

April has an interview with Professor Jordan Perry (David Warner). He is a scientist with Techno Global Research Industries or TGRI for short. The interview gets the attention of Splinter (Kevin Clash). Splinter gathers Michelangelo (Michelan Sisti), Donatello (Leif Tilden), Raphael (Kenn Scott) and Leonardo (Mark Caso) together and explains to them that TGRI was the company responsible for creating the green ooze that, fifteen years ago, turned the ordinary turtles into what they are now. They decide they need to talk to Professor Perry for more information on their past.

As April is winding up her interview her assistant Freddy (Mark Doerr) finds a mutated dandelion. Freddy is a spy for Shredder. He returns to the junk yard to show Shredder the giant mutated flower. Shredder also wants to talk to Professor Perry. Shredder manages to get his hands on both the last canister of ooze and the Professor. Shredder intends on using the ooze to create a race of mutants. He starts with a wolf and a snapping turtle. The wolf is mutated into Rahzar (Mark Ginther) and the snapping turtle into Tokka (Kurt Bryant). Shredder sets them loose on the turtles and on New York.

“Teenage Mutant Ninja Turtles II: The Secret of the Ooze” was released in 1991 and was directed by Michael Pressman. It is a superhero martial arts comedy. It is the second film in the original franchise trilogy.

The film was dedicated to Muppets creator Jim Henson, who died less than a year before its release. Henson's Creature Shop created the animatronic creature costumes for the film. The building used as the entrance to April's apartment building is the New York office of Jim Henson's Creature Shop.

The filmmakers got a lot of flak from parents about the amount of violence in the first TMNT movie so for this one the turtles didn’t use their weapons for most of the movie. They were kinder, gentler fight scenes. Shredder himself doesn’t do much in the way of fighting either. He mostly stands around watching other ninjas and creatures fight.

Ernie Reyes Jr. was Donatello's fight double in the first film, “Teenage Mutant Ninja Turtles” 1990. The film’s producers liked Reyes so much they created the role of Keno for him. Casey Jones does not make an appearance in this film. Judith Hoag was replaced by Paige Turco as reporter April O’Neil.

Vanilla Ice has a cameo and performs a Ninja Rap as the Turtles dance to it.

Both the first and the second Teenage Mutant Ninja Turtles film were censored in the UK due to usage of forbidden weapons (the nunchuku). The edits were waived for the DVD release in 2002. The German versions weren’t censored visually but funny cartoon sound effects were added to soften the violence of the fight scenes.

The voices of the animatronic turtle characters were Brian Tochi as Leonardo, the leader, in the blue bandana, Robbie Rist as Michelangelo, the fun loving turtle, in the orange bandana, Adam Carl as Donatello, the brains, in the purple bandana and Laurie Faso as Raphael, the rebellious, in the red bandana. As for the other animatronic characters, Kevin Clash does the voice of Splinter the sensei rat and father figure for the turtles. David McCharen is Oroku Saki/the Shredder. Michael McConnohie is Tatsu. Frank Welker as Tokka and Rahzar the mutated snapping turtle and the mutated wolf.