As previously reported, Allison Janney will guest star on this week's episode of Lost as... someone.

The former West Wing stalwart - who will appear alongside Matthew Perry on this fall's Mr. Sunshine - will play a pivotal role on "Across the Sea," though the actress (and everyone involved with the show) is mum on what that is.

We had speculated that Janney would portray The Man in Black's mother, as this week's episode explores the relationship between him and Jacob. (Watch a clip from it NOW.)

But this photo makes it appear as though her character is more closely associated with Jacob. Any theories on who she could be?

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