Michelangelo befriends Leatherhead, an unstable mutant alligator who possesses a strange piece of Kraang technology, but the other Turtles aren’t sure whether Leatherhead is a friend or a foe.

The Turtles must brave the bizarre world of Dimension X to save the enslaved people of New York. Part 1

Part 2

The Shredder kidnaps and experiments on the Mighty Mutanimals.

The Turtles, their 1987 counterparts, April and the Mighty Mutanimals must work together to stop 80s' Shredder and Krang from destroying the world. Meanwhile, Bebop and Rocksteady are faced with a difficult and life-changing decision.