Casey Jones has run into a major problemhis arch-enemy, Hun, leader of the Purple Dragons, has allied himself with the Shredderand gained a new power in the process, upsetting the balance of the streets! Luckily, Casey has friends to turn to when the going gets tough: the Teenage Mutant Ninja Turtles! While our heroes are dealing with this newly evolved threat, three foul fowl with an agenda involving April ONeil materialize in Manhattan. Theres just no rest for the good guys these days!