When two seemingly unrelated murders point to a mole in the Met, Assistant Commisioner Corrigan turns to DI Hanlon, a policewoman with a ruthless disregard for the rules. Detective Inspector Hanlon. She'll break but she won't bend. A woman with a habit of breaking the rules and a fierce loyalty to the few people she respects. Her boss, Corrigan. Looks like a street copper promoted above his ability. Underestimate him at your peril. Enver Demirel.

Known in the boxing ring as Iron Hand. Now soft and gone to seed. But he would do anything for Hanlon. Now the kidnap of a 12-year-old diabetic boy has blown the case of some missing children wide apart and the finger is pointing at the heart of the Met. Corrigan sends in the only cop in his team who would care more about the life of a boy than about her own career. Hanlon. And then he sends Demirel to spy on her.