Hannah plays DI Jack Cloth, who is called in to investigate an apparent series of serial killings alongside his new partner, DC Anne Oldman, described as a "plucky, no-nonsense sidekick". Playing with the cliches and conventions of British police dramas, subplots include Cloth dealing with visions of his dead wife and the bisexual DC Oldman coming to grips with her feelings for both her female fiancee and Cloth.

Belinda Douglas is a famous politician who is attacking the government on not being transparent enough. She's married to Jack, but has not always been faithful. Today she can't resist the urge either and picks up Jenna as one-night-stand. The next day Belinda has to leave early and tells Jenna where to find the keys. But the keys accidentally fall behind the door and Jenna is locked inside. As time is running out, she decides to check some personal belongings of Belinda. Then fate strikes.

The fascinating story of John Harrison who, in the 18th century, believed he could make a clock that would work on board a ship—and so solve the problem of finding longitude at sea.

Jack Frost is a gritty, dogged and unconventional detective with sympathy for the underdog and an instinct for moral justice who attracts trouble like a magnet. Despite some animosity with his superintendent, Norman “Horn-rimmed Harry” Mullett, Frost and his ever-changing roster of assistants manage to solve cases via his clever mind, good heart, and cool touch.