Fringe

Ari Graynor, most recently seen as Kat Dennings' drunk best friend in Nick & Norah's Infinite Playlist, has been chosen to portray the younger sister of Anna Torv's Olivia on Fringe.

The hilarious actress will appear in a minimum of three episodes, according to Michael Ausiello. Look for the first to air next month.

"She's dealing with some man trouble back home," said a show source, who said Olivia's sister would crash at her place for the duration of her visit. "But the exact nature of that trouble isn't clear."

Ari Graynor (left) does resemble her soon-to-pretend sister on Fringe, Anna Torv.