Supernatural

Mark Sheppard is coming to Supernatural.

As first reported by Mo Ryan of The Chicago Tribune, the actor will portray a "pivotal" demon named Crowley in this season's 10th episode.

The installment, titled "Abandon All Hope..." is the final hour of Supernatural in 2009. The show will take a month-long hiatus before returning in 2010.

But it will at least go out with a bang, as the episode is "epic" and will "definitely... have the fans on the edge of their seats going into the holiday 'hellatus,'" Ryan's source said.

Sheppard has recentlg guest-starred on Burn Notice, Leverage, Dollhouse and Warehouse 13.