In the latest episode of "Castle," Beckett was faced with the unthinkable. Did Castle commit murder? Evidence kept mounting against him, and for a moment it looked like everyone -- including Beckett -- at least entertained the possibility that he was a killer. Of course, for him to have committed the murder, he would have also had to be cheating on Beckett, so she was faced with even more to struggle with.

But the truth proved far more nefarious. It was, as Castle kept claiming, an elaborate set-up. But who would go to such lengths to set Castle up for murder? How about Jerry Tyson AKA the serial killer 3XK?

Not seen for years, this old case came back to haunt Beckett and Castle in a huge way. But as the chase ensued, Tyson actually left evidence of all he'd done to frame Castle, revealing perhaps a different endgame. When they finally came face-to-face with Tyson, the killer got the upper hand and had Beckett as a hostage.

But Castle managed to get the drop on him, shooting Tyson several times. He dropped into the water, though no body was found. No body means 3XK is probably still out there, with Buddy TV thinking this result was his plan all along. TV Fanatic agreed, further speculating that fans probably won't be waiting as long this time before he shows up again.

"Castle" airs every Monday at 10 p.m. ET on ABC.

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  • Castle 100th Episode

  • Castle 100th Episode

  • Castle 100th Episode

  • Castle 100th Episode

  • Castle 100th Episode

  • Castle 100th Episode

  • Castle 100th Episode

  • Castle 100th Episode

  • Castle 100th Episode

  • Castle 100th Episode

  • Castle 100th Episode

  • Castle 100th Episode

  • Castle 100th Episode

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