"Delivery driver Kang Han-gil has spent every waking moment trying to save his father, who has turned into a zombie. Poverty and exhaustion weigh on him, but he refuses to give up.
Then someone from his past reappears, Shin Midum, a man Han-gil hoped never to see again. Calling himself a “zombie caretaker,” Midum claims he can cure Han-gil’s father with a new experimental drug. But there is a price, and his demand is unsettlingly simple, he wants Han-gil in his bed.
Before Han-gil can decide whether to accept, disaster strikes. His zombified father escapes, the apartment complex collapses into chaos, and the entire building becomes a nest of the undead. Trapped together, Han-gil and Midum have no choice but to rely on each other.
With personal grudges simmering and survival on the line, can these two men escape the nightmare closing in on all sides, or will the past consume them before the zombies do?"