Stana Katic Stana Katic

[WARNING: The following story contains spoilers from Monday's episode of ABC's Castle. Read at your own risk.]

On Castle, some of the ghosts from Detective Kate Beckett's past just won't stay buried.

Beckett (Stana Katic) was reminded of that in a big way on Monday's episode, when she was asked to go on a simple undercover operation to bust a drug ring. There was just one problem: Although Beckett was told she was posing as a drug courier named Elena, she soon learned that the person she was impersonating was actually an assassin! Although Beckett managed to maintain her cover long enough to carry out a "hit" (who knew items in your pantry could make fake blood so quickly!) the jig was up when Beckett came face-to-face with drug lord Lazarus — who just so happened to be Vulcan Simmons, a one-time suspect in Beckett's mother's murder.

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Once Beckett was identified, she was taken out to be executed. However, just before Simmons' henchman could kill Beckett, the real Elena came to her rescue, sparing Beckett's life at the behest of "Lazarus." But during a post-operation debriefing, Beckett learns that the drug money is being laundered to fund a heavyweight politician. Although the money is untraceable, Beckett knows who the real Lazarus is: Senator William Bracken (Jack Coleman), the man responsible for Beckett's mother's murder.

"[The episode] gave us a chance to re-mythologize Bracken," Katic tells "We wanted to reintroduce him to the audience in a way that would kind of validate the threat that we had set up for so many seasons."

Indeed, now that Bracken has saved Beckett's life — evening the score from when Beckett thwarted an assassination attempt against the senator last season — creator Andrew W. Marlowe says Beckett must think differently about how to proceed with Bracken. "They've had this détente because, to the best of Bracken's knowledge, Beckett has information that will sink him," Marlowe says. "But this means if something else happens in the future, if these two come into contact, the gloves are off. That Sword of Damocles hanging over her head has to give her a sense of unease."

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