Castle Exclusive: Mad Men's Cara Buono Cast as Woman From [Spoiler]'s Past

Someone is due for a blast from the past when Cara Buono serves up trouble — or at least Irish whiskey — on Castle.

TVLine has learned exclusively that Buono — who memorably played Mad Men‘s formidable Faye Miller aka she who should have been Don Draper’s second wife — will guest-star in a March episode of the ABC drama as Siobhan O’Doul, a(n obviously) beautiful bar owner who has found herself in too deep with the Staten Island Mafia.

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But here’s the juicy part: When a murder case involving the Irish mob leads Beckett & Co. to Siobhan, we will discover that she shares a mysterious past with… Detective Ryan (played by Seamus Dever), who is now very married and angling to make a baby with wife Jenny.

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Since her well-received Mad Men run, Buono has guested on shows such as Hawaii Five-0 and A Gifted Man, and appeared in the well-watched Lifetime telepic Drew Peterson: Untouchable.

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