Jupiter Jim Ahoy! Rise of the Teenage Mutant Ninja Turtles : Season 2 Episode 10

Having gotten bored of Splinter's Lou Jitsu stories, the Turtles head to a convention and meet Marcus Moncrief who portrays their favorite sci-fi movie character Jupiter Jim. When they go to his apartment, they find that he has started to see the different trapped fans as the aliens that Jupiter Jim fought in the movies and comics where Marcus has become more immersed in his character to the point he thinks he is actually Jupiter Jim.