William Monk’s investigation of smuggling on the Thames is disrupted by customs officer McNab, who claims to know damaging details about Monk’s forgotten years in California. When a murder and a disputed cargo place Monk under suspicion, fragments of his past become evidence that others can shape against him.
Hester and the River Police help Monk reconstruct events from San Francisco and identify who has carried an old grievance to London. The case tests whether memory can establish guilt and whether revenge has turned a former enemy into the architect of a present crime.