Is it the beginning of the end for Castle and Beckett?

In Monday’s Castle (ABC, 10/9c), the duo’s romance is dealt a potentially devastating blow when Castle emerges as a suspect in a gristly ritualistic killing — forcing Beckett to wonder how well she really knows her partner in crime and passion.

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Press PLAY below and watch Esposito interrupt a super-cute “Caskett” moment to drop the bomb on Kate’s lap.