When Channel 3 Eyewitness News reporter April O'Neil is attacked by thieves, the Teenage Mutant Ninja Turtles engage in their first combat situation, striking the thieves down and saving April,...

When Channel 3 Eyewitness News reporter April O'Neil is attacked by thieves, the Teenage Mutant Ninja Turtles engage in their first combat situation, striking the thieves down and saving April, whom they take to their sewer lair. Upon meeting Splinter, the Turtles' sensei, the secrets of their origins are revealed. While the Turtles come to befriend April and Raphael encounters the vigilante Casey Jones, the Foot Clan (a gang of thieves stemming from Japan under the leadership of "the Shredder"), closes on the Turtles' lair and captures Splinter. In an ambush on April's store, Raphael is put into a coma. Forced into retreat, the Turtles, along with April and Casey, leave for an estate belonging to April, where they spend some time healing and training. Upon returning to New York, the Turtles wage war on the Foot Clan. With the aid of Danny Pennington, the son of Charles (April's boss), they free Splinter and confront the Shredder (who is revealed to be Oroku Saki, the man who slew Hamato Yoshi, Splinter's former master) in a rooftop duel. In the end, the Shredder is thrown off the rooftop by Splinter and crushed in the back of a garbage truck by Casey Jones.