Phil Newton’s review published on Letterboxd:
Private Kang (Jang Dong-gun) is a border guard who mistakenly shoots and kills a civilian. The resultant fall out turns the dead man's girlfriend crazy and affects Kang, leading to his eventual discharge. But Kang can't let go and returns to the border, armed and out of control. A suitably bleak drama about the South Korean military from Kim Ki-duk.