S03E08 - The Fifth Turtle
Synopsis
Dressed in their human disguises, Donatello and Raphael venture out of their Turtle lair to buy supplies to make pizza. On their way back, via what they believe to be a shortcut, they are "intercepted" by a gang of young street Punks. Suddenly, a young boy wearing a Turtle costume, and who calls himself Zack: "Master Ninja Turtles and the Scourge of Evil Doers", drops in out of nowhere. As he prepares to defend Donatello and Raphael, he falls flat on his face, allowing the real Turtles to dispatch the punks with ease. Afterwords, Zack explains how he wants to help them fight crime -- but Raphael tells him that he is more of a menace than a crime fighter. The kid leaves in a huff, picking up Donatello's Turtle-Com -- which he had lost in the scuffle with the would-be attackers.