Chao Yang is the number one student at his school, but he has a complicated family situation. He hangs out with two "bad" kids from an orphanage. They go to the mountains to take pictures. Chao Yang takes a video of Pupu singing while they are on the mountain and captures a murder scene.

Chao Yang realizes that he knows the murderer. Pupu threatens Chao Yang's stepsister so she doesn't bully him, but somehow she ends up dead. The police officer hears her fall as he was catching Yan Liang.