Steve Zahn has boarded Fox's "War for the Planet of the Apes," the sequel to last year's blockbuster "Dawn of the Planet of the Apes."

The "Treme" and "Dallas Buyers Club" actor joins a cast that already includes Woody Harrelson and Gabriel Chavarria.

Matt Reeves, who helmed "Dawn of the Planet of the Apes," is returning to direct, once again from a script by Mark Bomback. Although no story details have been revealed, Variety reports Zahn will play an ape. Harrelson is set to portray a villain named the Colonel.

Fox rebooted the classic sci-fi franchise in 2011 with "Rise of the Planet of the Apes," which grossed more than $481 million worldwide. "Dawn" far exceeded that tally, banking more than $708 million.