SOMEONE on Fox’s “The O.C.” will die this week and it could be Mischa Barton’s character, Marissa.

Or not.

Rumors have been swirling for weeks that producers have written Barton out of the show, but the truth has been kept so secret that not even staffers who work on the show know the answer.

In fact, to keep a lid on the final moments of this season’s finale, producers filmed several different endings. In one, Marissa is apparently killed off.