Will Arnett has signed on to play one of the leads in Paramount and Platinum Dunes' Ninja Turtles reboot. The actor's role is being kept a secret, although it was confirmed that he is not playing Casey Jones, one of the Turtles' human friends, a character that has yet to be cast.

The Hollywood Reporter made this casting announcement, and in the same story, they indicate that Megan Fox, who signed on last month, is playing April O'Neil. This has not been confirmed by Michael Bay or the studio.

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Alan Ritchson (Raphael) Pete Ploszek (Leonardo), Jeremy Howard (Donatello), and Noel Fisher (Michaelangelo) are playing the turtles. Other roles yet to be cast are Splinter (a sewer rat and the Turtles' martial arts master) and the villainous Shredder. Could Will Arnett be playing one of these two characters?

Jonathan Liebesman (Battle: Los Angeles, Battle: Los Angeles) is directing from a screenplay by André Nemec and Josh Appelbaum (Mission: Impossible Ghost Protocol). Michael Bay is producing along with Bradley Fuller, Andrew Form, Jason Reed, Galen Walker, and Scott Mednick.

It isn't known when production will begin.