Following the commencement of Operation Barbarossa, a unit of the Wehrmacht under the command of Capt. Klaus Woermann occupies an uninhabited citadel in Romania to control the Dinu Mountain Pass. Two soldiers attempt to loot a metallic icon within the keep but accidentally unleash a spectral entity, which kills them. The being, known as Radu Molasar, proceeds to kill several more soldiers in the following days and begins to take corporeal form. A detachment of Einsatzkommandos under the command of the sadistic SD Sturmbannführer Eric Kaempffer arrives to deal with what is thought to be partisan activity, executing villagers as collective punishment.