The Turtles, living in April O Neil's apartment, begin their search for a new residence, their last one having been discovered by the Foot Clan. Though they eventually find it in an abandoned...

The Turtles, living in April O Neil's apartment, begin their search for a new residence, their last one having been discovered by the Foot Clan. Though they eventually find it in an abandoned subway station beneath the sewers, Raphael becomes insistant in taking the fight to the Foot, and stalks off. After the Turtles watch Professor Jordan Perry of TGRI (Techno Global Research Institute) discusses the dumping of chemical wastes on the news, Splinter reveals more details about their origin, for it was TGRI Mutagen that mutated them from ordinary pet shop turtles to their present state. The Turtles then break into the TGRI building, where their attempt to track the last container of ooze falls short when Tatsu, Shredder's lieutenant, shows up with the Foot and gets away with it. Keno, a pizza deliver boy befriended by the Turtles, is sent by Raphael to infiltrate the Foot Clan. As Raphael helps him gain entrance, he discovers that Oroku Saki, the Shredder, is alive and well. Shredder captures Professor Perry and has him use the last remaining container of ooze to mutate a wolf and a snapping turtle into two mutants. Tokka and Rahzar, as Shredder names them, are set loose in downtown Manhattan. Shredder then threatens to loose them in Central Park unless the Turtles meet him in a duel. The Turtles meet him and his two mutations as per the Shredder's instructions. Tricking Tokka and Rahzar into swallowing retro-Mutagen ice cubes that would theoretically demutate them, they are then forced to confront the Foot in a battle that takes them inside a nearby club on the docks. Successfully demutating Tokka and Rahzar, Shredder's attempt to take a hostage in the club is thwarted by Keno, who blasts him out of the club with the club's speakers. The Turtles head outside, where they search for the Shredder. They find him, but the Shredder has been horribly mutated into a 13-foot tall behemoth. Before they can even fight, however, this SuperShredder brings the pier he dragged the Turtles into on top of himself just as the Turtles escape