Glenn Morshower

24 alum Glenn Morshower has been tapped to guest-star in the second episode of Castle's new season, TVGuide.com has learned exclusively.

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Morshower will play Michael Reed, a former general who will stop at nothing to protect the secrets of his past. With Reed's military connection, could he be involved in Washington, where Beckett (Stana Katic) was offered a job in the Season 5 finale?

Morshower, who recurred on 24 as Secret Service agent Aaron Pierce, most recently had a multi-episode arc on NBC's Revolution.

Castle returns on Monday, Sept. 23 at 10/9c on ABC.

Additional reporting by Adam Bryant.