1927, Breslau, Poland: Two elaborate and sadistic murders are discovered within days of each other. The body of an unknown musician, bound and gagged, is found behind a false wall in a shoemaker’s workshop. The victim had been sealed in alive. Elsewhere in the city, the horrifically mutilated body of a locksmith is found. Next to each victim is a torn-out calendar page, with the day of the death marked in blood. Nothing else seems to connect the cases.