William Fichtner has joined the cast of Teenage Mutant Ninja Turtles as, "a lead with iconic stature within the Turtles mythology." Could William Fichtner be playing the main villain Shredder? Or perhaps the Turtles' human friend Casey Jones? We don't know for sure as of yet, but hopefully this mystery is solved soon.

Megan Fox stars as journalist April O'Neil, with Alan Ritchson (Raphael), Pete Ploszek (Leonardo), Jeremy Howard (Donatello), and Noel Fisher (Michelangelo) portraying the turtles through motion capture suits, as we showed you earlier today. Will Arnett also stars as April O'Neil's cameraman Vernon Fenwick, with Danny Woodburn playing the turtles' master Splinter.

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Jonathan Liebesman (Battle: Los Angeles) is directing from a screenplay by André Nemec, Josh Appelbaum, Art Marcum, and Matt Holloway, with Michael Bay producing through his Platinum Dunes company. We'll let you know as soon as more details surface regarding William Fichtner's character.

William Fichtner most recently starred in the indie comedy Wrong, and will next be seen in The Lone Ranger and Elysium this summer.