TV's heroes in a half-shell are set to return to Nickelodeon next month. The current incarnation of (more…) TV's heroes in a half-shell are set to return to Nickelodeon next month. The current incarnation of animated hit Teenage Mutant Ninja Turtles kicks off its second season on Saturday, Oct. 12 at 11 a.m./10c. In the first episode, "The Mutation Situation," the Turtles find out that alien Kraang has dropped mutagen canisters all over New York. Throughout Season 2, the heroes will have to recover those canisters before more mutants are created. Meanwhile, Kraang and Shredder have joined forces to stop the Turtles. Joining the cast this season is Josh Peck (Drake & Josh), who voices teenage hockey player Casey Jones, a rebel who enjoys taking on the bad guys. TMNT also stars Sean Astin (as Raphael), Rob Paulsen (Donatello), Greg Cipes (Michelangelo), Jason Biggs (Leonardo), Mae Whitman (April O'Neil), Hoon Lee (Master Splinter) and Kevin Michael Richardson (Shredder). Corey Feldman recurs as Slash.