In the last boxing match before his retirement, TAN Kai accidentally beats his teammate WANG Yao to death. WANG’s heart is donated to a young girl, LI Chuan. Guilt-ridden, TAN Kai decides to meet LI Chuan and they slowly develop a friendship. Suddenly LI Chuan’s body is starting to reject WANG’s donated heart and a new surgery is very expensive. To pay for his sins and the surgery, TAN Kai must put his boxing gloves back on one more time.