Ji Yeon is a successful lawyer and single mother to a seven-year-old girl. On her daughter's field day, Ji Yeon competes with other parents in a running race and almost comes in the first place. However, nowhere could she find the girl who's been watching and rooting for her mother to win. Later that day, Ji Yeon's receives a phone call from an anonymous man, who tells her he has her daughter read morein custody and proposes a deal. To see her daughter alive, Ji Yeon needs to prove a convicted murderer not guilty on his second trial, only within a week.