They're losers, but nice ones. Every day they sit at Yeri's bar, smitten by the young Chinese-Korean woman. Yeri doesn't have a preference. To her, they are equally sweet: Jongbin, a milk-drinking epileptic, Ikjune, a former petty criminal, and the introverted Jungbum, who fled from North Korea.

When an illicit arms deal goes bad, North Korean spy Pyo Jong-seong finds himself targeted not just by the South Koreans but also his own bosses.

Some time after completing his mandatory military service, a man receives a distressed call from one of his subordinates, who's also an old classmate.