Ji-eun, Seong-min, and So-young, all university classmates, are enjoying a night of drinking and games in their studio apartment. Ji-eun, having fallen asleep, awakens to a disturbance. She discovers Seong-min attempting to assault So-young. When his attempt is met with fierce resistance, Seong-min tragically kills So-young. In a state of panic, Seong-min then traps Ji-eun, who is now a witness to the horrific crime.