Finale Post Mortem: Castle Boss Says What Comes Next Is Tough, 'But It'll Be Fun Tough'

Warning: The following contains major spoilers from the Season 4 finale of ABC’s Castle. If you have not yet watched, turn away now. All others, proceed….

On Monday night in the Season 4 finale of Castle, all secrets were shared and all cards were put out on the table, as promised. But where did it all lead?

Working the murder of an Army vet, Beckett & Co. came to discover through DNA evidence that the shooter was the same guy who put a bullet in Kate’s heart a year ago — and thus he figures into the larger, deadly conspiracy surrounding Johanna Beckett’s years-ago killing.

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But for Kate to rattle that hornet’s nest again would certainly lead to her own demise — a fact that Rick has known but kept to himself. And in the finale, he made clear to Kate exactly why she needed to back away from this case.

Beckett was less than understanding. “I didn’t need protection; I needed a lead, and you sat on it for a year…. How the hell could you do this?!”

“Because I love you. But you already know that, don’t you,” Rick said, alluding to his Season 3 finale declaration which Kate has pretended to not remember.

They agreed to disagree, and Kate stayed on the case while Rick disclosed his intention to exit stage left, once and for all. But after a brutal rooftop throwdown with the shooter (played by Battlestar Galactica alum Tahmoh Penikett) — and backlash from Capt. Gates which led Beckett to not just turn in her badge, as Esposito did, but tender her resignation — a rain-soaked Kate showed up at Rick’s door to say three words again and again: “I’m so sorry.”

“He got away, and I didn’t care,” she explained. “I almost died, and all I could think about was you. I just want you.”

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And like that, one of TV’s biggest Will They/Won’t They couples fell into each other’s arms, and then (from all indications) into Rick’s bed. And not a moment too soon.

“In terms of storytelling, we felt like we were dangerously close to trying the audience’s patience – and we were starting to get impatient ourselves. We want to move on to new territory,” series creator Andrew W. Marlowe tells TVLine. “We feel like we wrung everything out of them not being in a relationship, so it’s time to put them in a relationship and in more, different fun.”

Fun however does not necessarily mean easy. “Relationships are tough, especially when the two people are fundamentally different people,” the show boss notes. “But I think it’s going to be fun tough – like when Sam and Diane got together on Cheers.”

Marlowe reports that the timing of the sexy new wrinkle “felt right” to not just him and his writing team but both of Castle‘s leads, Nathan Fillion and Stana Katic. “To not have done it now would have betrayed our covenant with the audience,” he states. “We’ve asked them to invest, and we would not be good storytellers if we did not pay off that investment.”

So, Castle fans: Happy? (And did you really have any doubt?)

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