When "Castle" returns for its eighth season, Kate Beckett (Stana Katic) takes on a new job, having just been named new captain of the 12th precinct. In newly released photos for the season premiere, fans will get to see how Castle (Nathan Fillion) and Beckett's team handle the promotion and what the couple will be up to when the show returns to ABC. 

In the stills posted on TVLine, a smiling Beckett is seen being applauded by Castle, Ryan (Seamus Dever) and Esposito (Jon Huertas) at the station, and some photos feature a first look at new characters Hayley (Toks Olagundoye) and a new member of the police force played by Sunkrish Bala. 

Beckett and Castle are also seen in a romantic moment as they share a kiss, but the two get back to business chasing after an unknown bad guy as Beckett holds her gun in front of her. 

TVLine reports that the season premiere is a two-part episode. The first, titled "XY," is told from Castle's point of view after his wife mysteriously goes missing; while the second, titled "XX," is told from Beckett's side of things, which reveals what happens when she disappears. 

In an interview with TVLine, co-showrunners Alexi Hawley and Terence Paul Winter talked about the upcoming season and the premiere episode. At the time they filmed the premiere, Katic was filming a movie, and it was revealed that her scenes in the first part were taped right after they finished filming scenes with everyone else. 

"It actually ended up being a great opportunity," said Hawley. "It allowed us to sort of bookend her in the first episode, create a great mystery of 'What's going on with Beckett?' that ultimately pays off in the second episode." 

Meanwhile, Winter said that the show's two-part premiere has been a fun experience for them as it allowed them to be more creative.

"The two-parter, we're really proud of what we did with this thing. It's going to be delightful," said Winter.

"Castle" season 8 premieres on Monday, Sept. 21, at 10/9c on ABC.