Castle Season 8: Ann Cusack Cast as Mystery Woman With Ties to

Private Practice alum Ann Cusack has landed a provocative guest-starring role in Castle‘s Season 8 premiere.

RELATEDCastle‘s Stana Katic Teases ‘Event’ that Shifts Season 8 Into ‘Higher Velocity’

TVLine has learned exclusively that the actress will appear in the second half of the two-part season opener as Rita, a member of a top-secret organization who drops into Beckett’s life with a unique set of skills… and an unexpected connection to Castle.

In addition to her Private Practice arc as the wife of Addison’s mother Bizzy, Cusack’s recent TV credits include episodes of Backstrom, Masters of Sex, Scandal and Hart of Dixie.

RELATEDCastle Season 8 Adds The Neighbors’ Toks Olagundoye as Series Regular

Previously this summer, Castle added Toks Olagundoye (The Neighbors) in the series regular role of onetime Scotland Yard officer Hayley Vargas, while Sunkrish Bala (The Walking Dead) will recur as a high-strung tech analyst.

Castle opens its eighth season on Monday, Sept. 21.

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