"The gruesome murder of a young French physician draws aristocratic investigator Sebastian St. Cyr and his pregnant wife, Hero, into a dangerous, decades-old mystery as a wrenching piece of Sebastian's past puts him to the ultimate test. Regency England, January 1813: When a badly injured Frenchwoman is found beside the mutilated body of Dr. Damion Pelletan in one of London's worst slums, Sebastian finds himself caught in a high-stakes tangle of murder...