Something big is coming on Castleaccording to star Stana Katic.

In a new interview with Deadline, Katic revealed that an "event" will be taking place that "shifts the entire season into a higher velocity," setting everything up for the rest of the season.

The inciting incident will take place within the two-episode premiere that the actress calls "brother and sister." Each episode will reveal Castle and Beckett's perspective on that particular event. When we last left the couple Beckett was considering an offer to run for the New York State Senate. While Katic revealed little about what the new season will hold, she certainly seems excited about what's in store.

"Part of the exciting thing about the new season is the way [new showrunners Alexi Hawley and Terence Winter] have envisioned the cosmic version of why the two characters have come together," Katic says. "It delves into the mythology of Rick's disappearance and memory loss as well as into what inspired Beckett to become a cop in the first place."

Hawley also offered fans a tease of what's to come on Monday:

Meanwhile, Katic will be returning to Castle with a new title under her belt: that of a producer on the show.

Castle returns Sept. 21 at 10/9c on ABC.

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