Jessica Tuck Jessica Tuck

True Blood's Jessica Tuck is stirring up trouble on the new season of Castle, has confirmed.

Tuck, who plays vampire-human liaison Nan Flanagan, will guest-star as a wealthy museum benefactor who becomes a suspect in a murder investigation, as first reported.

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The Killing's Kristin Lehman also guest-stars in the same episode as a sexy art insurance investigator who joins Castle (Nathan Fillion) and Beckett (Stana Katic) on the investigation that involves the theft of a sculpture. She also sets her sights on Castle, much to Beckett's chagrin.

Tuck, 48, is also known for her roles on One Life to Live, Days of Our Lives and, more recently, Super 8.

Castle returns Monday, Sept. 19 at 10/9c on ABC.