Hero Complex can confirm that Michael Keaton and J.K. Simmons have left Kong: Skull Island.

Reported first by Deadline, the site mentioned scheduling conflicts as the reason both actors exited the project. That’s two huge losses for the movie. Now only actor Tom Hiddleston and a giant ape remain attached to the film.

Director Jordan Vogt-Roberts’ Skull Island created a bit of a roar in 2014 at the San Diego Comic-Con when a teaser reel took Hall H’s audience by surprise. The King Kong origin story sneak peek was met mostly with enthusiastic cheers and better-than-expected nods of approval. The casting of Hiddleston, Simmons and Keaton only upped the genre fan cred.

But now two of the movie’s biggest stars are gone. It will be interesting to see who Legendary Pictures finds to replace them. That re-casting will need to happen soon as the principal photography for Skull Island is allegedly going to take place late this year.