Teenage Mutant Ninja Turtles (1987)

S03E36 Leatherhead Meets the Rat King

Title: Leatherhead Encounters the Rat King Plot: Leatherhead arrives in the city on a mission to find the Turtles. As he navigates the dark, winding sewers, he unexpectedly crosses paths with the Rat King, who accuses him of intruding on his territory.