French film set during the Algerian war of independence in 1959. Terrien (Benoit Magimel), an idealistic French lieutenant, has been posted to the mountains of Kabylia to take over the command of a platoon at an army outpost. Here he meets Dougnac (Albert Dupontel), a jaded sergeant. Their differences, and the brutal realities of combat, soon drive the two men to bitter enmity. Amidst the savagery of an undeclared war, they come to realise that their worst enemy is themselves.