在六年前，五位青年组成乐队，最后一次演出，遗憾中留下三人——吴珂、柴林和洪大方。他们因保管宝贵珠宝而逃脱匪徒之手，并将钥匙交给了离群的队友江颐格。年华过去，江颐格与杨赞失联，直到她的女儿小小在聚会上出现，惊悚地告诉众人她的母亲被杀。 Yang Zan, haunted by the possibility of being the culprit, takes in Small Xiao and Wu Feng when they seek refuge. Unfortunately, Tidy Lin is murdered, and under Yang Zan's persistent questioning, Hong Da Fang reveals the truth about their past. Just as chaos ensues, gunshots ring out, claiming another life - Hong Da Fang falls.
Blaming Wu Feng for the crime, Yang Zan becomes wary of Small Xiao's safety. When Small Xiao goes missing, he follows the trail with the key that she had kept for him. To his surprise, it is Autumn He who appears, reveling as one of the original gang members who had sought the treasure six years ago.
Autumn He takes Small Xiao hostage, demanding Yang Zan return the treasure within three days. In a race against time, Yang Zan uncovers the truth about the key and the whereabouts of his daughter. As Autumn He and the police close in, a fierce confrontation ensues, resulting in the tragic death of Autumn He's lover, Jiang Yong Ge.
In the aftermath, Yang Zan grieves for his losses, but Small Xiao's determination to speak up changes everything. Guided by her courage, he begins anew, and several years later, Small Xiao blossoms into a talented violinist.
