After a friend's son is found dead, Soviet secret-police officer Leo Demidov (Tom Hardy) suspects his superiors are covering up the truth. When Leo dares to raise questions, he is demoted and exiled to a provincial outpost with his wife (Noomi Rapace). There, Leo soon discovers other mysterious deaths with similar circumstances and convinces his new boss (Gary Oldman) that a deranged serial killer is on the loose—and must be stopped before he strikes again in this electrifying thriller.