A robot warrior, known as the Mobile Armored Computerized Combatant (M.A.C.C.), arrives from 400 years in the future in 20th-Century New York. He befriends the Turtles, but Shredder and Krang are looking to bring him to their side, at any means necessary.

Krang and Shredder's plan to flush out the Turtles from the sewers leaves the city flooded with water (and creatures!) from the ocean.