As Jacob on Lost, Mark Pellegrino portrays a seemingly ageless character, one whose intentions are unclear.

At least half of that description can be applied to his new role on Supernatural.

Sources confirm to Michael Ausiello that the actor is joining the cast of The CW drama in the role of the Prince of Darkness himself, Lucifer. He'll debut on September 10.

Earlier this week, it was announced that Adrianne Palicki would reprise her role of Jessica on the show. We'll be tuning in for that episode.

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.