Jack Coleman Jack Coleman

Could the mystery of Castle's disappearance be adding another piece of the puzzle?

Castle's two-part premiere, beginning Sept. 21, has added another returning guest star: the suspicious and no-good William Bracken, played by Heroes Reborn actor Jack Coleman. Last we saw that senator who had ordered the hit on Beckett's mother's murder, he was humiliated publicly during one of his own press conferences. Now Bracken will "be back in a surprising way," co-showrunner Terence Paul Winter told TVLine.

The first part of the show's Season 8 premiere, titled "XY" will also be introducing new characters, Hayley Vargas, a security specialist played by Toks Olagundoye, and Vikram Singh, a tech analyst played by Sunkrish Bala.

Castle's new season will explore how Castle and Beckett were meant to be

Ann Cusack will also be appearing in Part 2, as Rita, a member of a top-secret organization who is somehow connected to our favorite mystery writer.

What do you think will be going down in Castle's Season 8 premiere? Leave us your thoughts in the comments.

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