n the heat of the St Petersburg summer of 1868, a doctor's wife and son are found dead, victims of a suspected poisoning. The doctor is arrested, but when further bodies are discovered it sets investigator Porfiry Petrovich on a thrilling and dangerous chase through the dark heart of the city, encountering aristocrats, soldiers, beggars and prostitutes as he hunts down a ruthless and elusive killer. 'Teems with tsarist spies, would-be revolutionaries and a stifling bureaucracy that frustrates ordinary Russians at every turn.' Sunday Times