Teenage Mutant Ninja Turtles (1987)

S3E18 Cowabunga Shredhead

After a glitch in the system, The Shredder begins to believe he is Michaelangelo. Confused and disoriented, he starts adopting the Turtle's carefree attitude and quirky behaviors, much to the surprise of everyone around him. Meanwhile, the Turtles must navigate this bizarre situation, trying to figure out how to set things right while dealing with the unpredictable antics of their archenemy, who now thinks he's one of them. As chaos ensues, friendships are tested, and unexpected lessons are learned.