Donnie and Wingnut go to restore power to the Lair but get trapped by the East River 3; the water is rising and they're not alone, there's a monster down there with them.

The East River 3 are on the verge on victory; The Turtles and Mutanimals must team up to stop them, but not everything is as it seems, they need to discover what is the pearl and why does Goldfin want it.