Captain Gabriel Lacey begins Spring 1818 preparing for a duel. But while he focuses on the affair of honor, darkness, greed, and death stalk the streets of London and bring tragedy to a family Lacey has grown close to. With the aid of Lucius Grenville, London's most famous dandy, and Brewster, a ruffian employed by an underworld criminal, Lacey's investigation takes him from the elegant mansions of Grosvenor Square to the squalid lanes of Seven Dials,...

Captain Lacey is asked by Peter Thompson of the Thames River Police to help him investigate a cold case - the murder of a woman found near the docks Thompson patrols. The investigation was sidelined, considered unsolvable, but Thompson has long wished to find her killer. Captain Lacey joins him in the hunt, entering a part of society that is closed to outsiders. Meanwhile, he must deal with his daughter's debut and more developments in his new domestic...