Algeria, 1959. High in the mountains of Kabylia, Terrien (Benoét Magimel), an idealistic lieutenant takes over the command of a platoon at a French army outpost. Here he meets Dougnac (Albert Dupontel), a cynical sergeant. Their differences and the harsh realities in the field drive the two men to breaking point. Lost in an undeclared war, they discover that their worst enemy is themselves.