Raphael's pet turtle, Spike, is exposed to mutagen and changes into a hulking brute. He then sets out on a vendetta against Raph's brothers.
Baxter Stockman traps the Turtles in a maze with Fishface and Dogpound.
The Turtles go all out to stop the Kraang invasion for a final time.
The Turtles come face to face with a wannabe hero known as The Pulverizer.
When April's science project attracts the Kraang's attention, the turtles must step in to save the day.
While Raphael takes a turn leading the group, Leonardo ventures elsewhere and meets Karai, a female ninja with dark secrets.
The Turtles have their hands full when a new foe named The Rat King plans on taking over New York City. Unfortunately, The Rat King is also planning on controlling Splinter's mind.
Michelangelo befriends 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.
When their home is attacked by Bradford, the Turtles must step up and defend the only home they've ever known.
The Turtles spring into action when April receives a distressing phone call from her father. Now it's up to the team to stop the Kraang from detonating a bomb in the city.
Leonardo struggles with his past when an old enemy, Xever, comes back to attack a noodle shop.
While searching for a missing scientist, Donnie and April find a psychic monkey instead.
Chaos ensues when Donatello creates Metalhead, a robotic turtle to fight alongside the rest of the group.
The Turtles meet a devious inventor named Baxter Stockman. But is this man all that he appears to be?
Michelangelo accidentally befriends Chris Bradford, a henchmen who's secretly working for Shredder!
When a video surfaces showing the Turtles topside, Master Splinter worries that their secrecy will be compromised. Meanwhile, Raphael struggles to keep his anger problems in check.
Alicia defends a client charged with protecting the identity of the creator of an illegal currency. Meanwhile, Elsbeth still defends Will as he's a suspect in a bribe with several judges. Kalinda is also trying to find a way to help Will but finds out he is not the only party ( Cary, Dana & Wendy Scott Carr ) that might need her help.moreless
The series finale of Fraiser finds Martin and Ronee on the verge of matrimony, and Niles and Daphne preparing for labor. Meanwhile, Frasier prepares for his career in a new city.