After Po is tapped to become the Spiritual Leader of the Valley of Peace, he needs to find and train a new Dragon Warrior, while a wicked sorceress plans to re-summon all the master villains whom Po has vanquished to the spirit realm.

After years of being sheltered from the human world, the Turtle brothers set out to win the hearts of New Yorkers and be accepted as normal teenagers through heroic acts. Their new friend April O'Neil helps them take on a mysterious crime syndicate, but they soon get in over their heads when an army of mutants is unleashed upon them.