To prove that Turtles can be friends with humans, Michelangelo uses a social networking site to befriend a famous martial artist who is secretly Shredder's top lieutenant.

When Donatello loses confidence in his bo staff as an effective weapon, he constructs Metalhead, a fully armed robotic turtle based on Kraang technology.

After April receives a warning from her imprisoned father, she and the Turtles embark on a mission to save him and stop The Kraang from detonating a mutagen bomb in the city.

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 get their first look at high school when April's school project draws attention from the Kraang.

While trying to foil a Kraang invasion plot, the Turtles are hunted by a giant cockroach.

While the Turtles are infiltrating an undersea Kraang base, the Foot Clan attempts to capture April.

The turtles engage in a difficult battle, as they make a desperate assault on TCRI to shut down the Kraang portal.