Near the end of the war in Germany, GI Steve Boland, a self-described "sharp-operator", meets a German girl, Ilsa, and they fall in love. Ilsa's brother Karl, whom she has not seen in three years, and his fellow Nazi Ludwig visit Ilsa. Karl proudly informs her that he and Ludwig are "Werewolves", a group of Nazi assassins parachuted behind Allied lines for the purpose of killing Allied High Command officers. She and Steve go to Army Intelligence with their information, where Steve is immediately arrested for being A.W.O.L. Captain Melton of Army G-2 intervenes on Steve's behalf, as G-2 has had a suspicion about the existence of the "Werewolves" but no concrete info before now.

Steve Boland (Charles Bronson) est un criminel mineur cynique enrôlé dans l'armée américaine pendant la Seconde Guerre mondiale. Il a une carrière militaire peu spectaculaire avec son passé criminel lui causant des ennuis, mais il prend ses droits lorsque son expertise criminelle lui offre des opportunités inégalées pendant l'occupation américaine de l'Allemagne.

Nachdem er aus dem Gefängnis entlassn wird, geht Steve Boland zur Armee wo er sofort in das Kriegsgebiet nach Deutschland versetzt wird. Dort entwickelt sich der Einzelgänger langsam zum Helden