5x11 - Teenage Mutant Ninja Turtles

The demonic Shredder has transformed New York City into a nightmare version of Feudal Japan and the rest of the modern world is next! But the Turtles have a plan, and if it takes allying themselves with some of their former enemies to bring the fight to the Shredder, so be it... because if they fail, all life as they known it will cease to exist.