June 1812. Napoleon begins his invasion of Russia. But among the troops of the Grande Armée is a savage murderer whose bloodlust is not satisfied in battle.
When an innocent Polish woman is brutally stabbed, Captain Quentin Margont of the 84th regiment is put in charge of a secret investigation to unmask the perpetrator. Armed with the sole fact that the killer is an officer, Margont knows that he faces a near-impossible task and the greatest challenge of his military career.