Sun-young is a popular radio DJ for a cinema music program that is aired live at midnight. She is a perfectionist who has built a successful career for the past 5 years, but when her young daughter needs a surgical operation overseas, the single-mom decides to quit. She prepares for her final show from song selections down to the smallest details. During the show, she receives a call from a listener named Dong-soo. He tells her that she must follow his orders while she hosts her live radio show, or her family's lives will be at stake, and threatens that she can't tell anyone. Without knowing what he wants or why this is happening to her, she continues her 2-hour radio program as the situation quickly escalates.