Joelle Carter

We're not sure Boyd Crowder's going to be happy about this casting news.

Justified star Joelle Carter has booked a guest role on ABC's Castle, TVGuide.com has learned exclusively.

On Castle, Carter — who plays Ava, the wife and co-conspirator of Walton Goggins' criminal kingpin Boyd Crowder on the critically loved FX drama — will portray Maggie Ingram, the long-time girlfriend of a death row inmate who is on the verge of being executed.

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Will Maggie lean on Castle (Nathan Fillion) and Beckett (Stana Katic) to re-investigate her beau's case before he's put down? (We'll have to see if Maggie is as persuasive as Ava is with her shotgun.) Additionally, I hear Alexis (Molly Quinn) is heavily involved in this case.

Besides her role on Justified, Carter has appeared on Grey's Anatomy, Body of Proof and NBC's short-lived Prime Suspect.

Castle
returns for its sixth season Monday at 10/9c. Carter is slated to appear in the new season's seventh episode, "Life Father, Like Daughter." An airdate has not been scheduled.