Sorcery. Treason. Madness. And, of course, murder most foul . . .A shattering accident places Archibald Clare, mentath in the service of Britannia, in the care of Emma Bannon, sorceress Prime. Clare needs a measure of calm to repair his faculties of Logic and Reason. Without them, he is not his best. At all.Unfortunately, calm and rest will not be found. There is a killer hiding in the sorcerous steam-hells of Londinium, murdering poor women of a certain reputation. A handful of frails murdered on cold autumn nights would make no difference . . . but the killings echo in the highest circles, and threaten to bring the Empire down in smoking ruins.The game is afoot . . .