Teenage Mutant Ninja Turtles — S1 E3 - Attack of the Mousers

When April O’Neil wakes up in the Turtle’s lair she has major trouble dealing with the reality of four giant talking Turtles and a Zen-master rat. She soon learns of the origin of the Teenage Mutant Ninja Turtles and they realize their common enemy is Baxter Stockman and his army of robotic Mousers.