'Castle' Sneak Peek: Guess Who's Behind Door No. 1?

Caskett’s days are coming to an end, so we’re savoring every last Castle scene that features departing star Stana Katic. In this exclusive sneak peek from the upcoming Castle episode “Much Ado About Murder,” Katic’s character, NYPD Captain Kate Beckett, is not happy about seeing her husband Richard Castle’s (Nathan Fillion) face pop up on the evening news as the lead of the murder investigation of a Hollywood superstar.

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But the lack of media control is really the least of Castle and Beckett’s problems. Turns out there could be clues to the murder at the Black Door, a “discreet” hotel where the star, Zane Cannon, spent the last two weeks with a mystery lady. Zane is dead, but his mystery date is still snoozing in the plush suite, so the NYPD pays her a visit.

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Take a look at the clip to see who the mystery lady is. We have a feeling this is one background check that won’t take Beckett too long to complete.

The “Much Ado About Murder” episode of Castle airs Monday, May 2 at 10 p.m. on ABC.