In the course of his tenure with the Thames River Police, Commander Monk has yet to see a more gruesome crime scene: a Hungarian warehouse owner lies in the middle of his blood-sodden office, pierced through the chest with a bayonet and eerily surrounded by seventeen candles, their wicks dipped in blood. Suspecting the murder may be rooted in ethnic prejudice, Monk turns to London's Hungarian community in search of clues but finds his inquiries stymied by its wary citizens and a language he doesn't speak. Only with the help of a local pharmacist acting as translator can Monk hope to penetrate this tightly knit enclave, even as more of its members fall victim to identical brutal murders. But whoever the killer, or killers, may be -- a secret society practicing ritual sacrifice, a madman on a spree, a British native targeting foreigners -- they are well hidden among the city's ever-growing populace. With the able assistance of his wife -- former battlefield nurse Hester, who herself is dealing with a traumatized war veteran who may be tangled up in the murders -- Monk must combat distrust, hostility, and threats from the very people he seeks to protect. But as the body count grows, stirring ever greater fear and anger among the Hungarian, resistance to the police also increases. Racing time and the rising tide of terror all around him, Monk must be even more relentless than the mysterious killer, or the echoes of malice and murder will resound through London's streets like a clarion of doom.