The new season of ABC's Castle will feature many surprises, including the return of one infamous character and a big evolution of another.

'Castle' Star Stana Katic Talks Huge Event In Season 8 That Puts Things In A 'Higher Velocity'

Season 8 of Castle will be a big one for the show. With Captain Gates (Penny Johnson Jerald) departing, new characters will enter the fold, including security specialist Hayley Vargas (Toks Olagundoye) and analyst Vikram Singh (Sunkrish Bala).

But the new season will also feature the return of Senator Bracken (Jack Coleman), the man responsible for plotting Beckett's (Stana Katic) mother's death. He will reportedly "be back in a surprising way," new Castle co-showrunner Terence Paul Winter told TVLine recently.

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He will be present in the two-part season premiere, as will actress Ann Cusack, who is playing Rita, a woman involved with a secret organization who gets involved with Beckett's storyline. She will also have connection with Castle (Nathan Fillion). Cusack will appear in the second part of the premiere.

It will be interesting to see how Bracken gets back into the fold, considering he was last seen in season 6 being shipped off to jail.

In other Castle news, it's looking like Alexis (Molly Quinn) will be growing up a bit in season 8. According to another TVLine report, Alexis might become a more sexual being in the new season. How will Castle respond to her daughter's evolution? Only time will tell.

Castle season 8 is set to premiere Monday, Sept. 21 at 10 p.m. ET/PT on ABC.

Tags: Castle television ABC