The Enemy (2011) ซับเกาหลี

The story begins a couple days after the war has ended. A group of Serbian soldiers in charge of clearing the fields from mines discovers a man sealed inside a factory's basement. A mysterious man says he is 'ours', he doesn't feel cold, isn't hungry and only asks for cigarettes. As soon as he is brought along, people start disappearing, and the infighting begins. Who is the mystery man?