Crime thriller set in Stalin-era Soviet Russia. In a state where crime isn't supposed to exist, pro-Stalin security officer Leo Demidov (Tom Hardy) begins to investigate a series of child murders. For his ignorance and betrayal of state policy, Leo finds himself demoted and exiled from the country he believed he was perfecting. Nevertheless, the persistent war hero pursues the case with only his wife Raisa (Noomi Rapace) for help. With his loyalty and beliefs shattered, Leo must try to find a killer who supposedly doesn't exist before his victim count rises further. But having been denounced, Leo may be in danger from a force far bigger than the free-roaming killer.