Castle season 8
Kate and Rick will celebrate their first wedding anniversary on a cruise ship in Castle season 8 winter  finale ABC

Castle season 8 winter finale is here and it promises to feature some sweet romance between Rick Castle and Kate Beckett as the couple celebrate their first wedding anniversary. But the mystery thriller by ABC will not go high on the closeness between the couple as there will be a serial killer looming large over their party, which is set on a cruise ship.

The synopsis of episode 8 titled Mr. & Mrs. Castle reads: Castle and Beckett investigate the murder of a cruise ship entertainer, only to find themselves trapped at sea with the killer.

In the previous episode, Rick plans a surprise for the love of his life ahead of their first wedding anniversary. TV Line reports that the mystery novelist will be close to uncovering the super-secret LokSat mission by Vikram Singh and Beckett.

The website also reports that there will be a huge fight between the couple where one of them will scream: "I just hope I didn't nuke my marriage."

In one of the sneak peek, the mystery novelist tries to mingle with the entertainers in an attempt to get some clues about the cruise murder. The winter finale will take different twists and turns as several truths will tumble out, including about the serial killer who has murdered one of the cruise dancers and is still roaming free on the ship.

Apart from juggling with the tricky and risky murder case, the couple will also have to deal with their share of personal troubles. Castle season 8 winter finale will air in the US on 23 November. Click here to watch the episode via live stream online in the US.