Eight people embark on an expedition into the Congo, a mysterious expanse of unexplored Africa where human greed and the laws of nature have gone berserk. When the thrill-seekers — some with ulterior motives — stumble across a race of killer apes.

After supervillain Shredder escapes custody, he joins forces with mad scientist Baxter Stockman and two dimwitted henchmen, Bebop and Rocksteady, to unleash a diabolical plan to take over the world. As the Turtles prepare to take on Shredder and his new crew, they find themselves facing an even greater evil with similar intentions: the notorious Krang.