In 1992, 18-year-old Hannah Taylor was kidnapped, and now a body, once believed to be hers, is proven to be another girl's. Hannah's mother, Madeline, an ex-alcoholic G.P., is prickly but admits to paying a twenty-thousand-pound ransom delivered by an-ex cop who was, in fact, her married lover. Jack suspects that this was a scam to part Madeline's former husband from twenty thousand pounds. The mystery intensifies when Jack traces Hannah, now married, who states that she left her mother a note to say she was going to a pop festival where she met her husband. It intensifies even further on the discovery that Madeline already knew Hannah's husband.

The UCOS team investigates the death of Eric Trimble, a soldier who was beaten to death in 1991. Their informant tells them that he and Eric, while still in the Army, were part of secret medical experiments that left the survivors paranoid. Their attempts to investigate those experiments come up against a military establishment that puts every possible in their way, including a visit from MI-5. As the investigation continues however, they discover several other possible motives including the fact that Eric was a bully and also gay. The fact that he is black also makes race a possible motive. Meanwhile, Brian continues to struggle with his alcoholism.