A murder at sea. One detective. No backup.

DI Rachel Harlow is off duty and stuck aboard a cruise ship with her twin teenagers and uptight parents. Determined to distract herself from the complicated mess – professional and personal – she’s left back at Northumbria Police HQ, she embarks on a flirtatious game with a stranger on board… until she finds him dead the next day.

With no eyewitnesses and no official investigation, Rachel digs into the murder alone, going strictly against the captain’s orders. Dead end after dead end, she’s met with lies and silence from the ship’s crew.

International waters allow people to play by different rules, but Rachel won’t let up. Even when it leads her to a crime ring just as dangerous as the one she’s left behind on land. But at sea, she has no team to back her up …