Guei, portrayed by Lin Cui, is a 17-year-old rural boy who ventures to Beijing in search of work. Alongside several peers from his hometown, Guei secures a position at a courier company where they utilize brand-new bicycles for their deliveries. The company manager, Xie Jian, informs them that since the bicycles are not yet their property, they'll receive just 20% of the commission. However, once they’ve completed enough deliveries to claim their bicycles, their earnings will increase to 50%. Within two months, Guei manages to earn the right to his own bike. Unfortunately, on the day he is to assume ownership, his bicycle is stolen while he is out retrieving a document. The manager dismisses Guei for failing to deliver the package, but upon Guei's desperate pleas, he reluctantly agrees to rehire him if he manages to recover the stolen bike.
In another part of the city, Jian, a schoolboy played by Li Bin, yearns for his own bicycle to ride with the girl he has a crush on, Xiao. His hopes are dashed when his father, Zhao Yiwei, postpones the purchase of a bike once again to prioritize a prestigious school for his younger stepsister, Rong Rong. Frustrated, Jian resorts to stealing money from his family and pays a second-hand dealer 500 yuan for Guei’s stolen bicycle.
While Guei embarks on a quest to locate his bike, his friend Mantis spots Jian with it. Guei attempts to reclaim his bicycle but is confronted by Jian and his group of friends. Tenaciously, Guei follows Jian home and manages to retrieve his bike from where Jian has hidden it. The manager fulfills his promise and rehires Guei. However, Guei's joy is short-lived as he soon finds Jian and his gang waiting for him at the courier company. In a desperate attempt to escape, Guei is pursued, beaten, and ultimately, his bike is forcibly taken from him again.
Returning home, a confrontation ensues between Jian and his father, who mistakenly accuses him of theft. In a fit of anger, the father punishes Jian, allowing Guei to leave with the bicycle. The next day, Jian and his friends locate Guei once more, leading to a tense negotiation where they agree to share the bicycle, alternating its use on different days. This arrangement holds until Jian discovers that Xiao has taken a liking to Da Huan, a bicycle freestylist. In a fit of jealousy, Jian retaliates and attacks Da Huan.
During their next encounter, Jian hands the bicycle back to Guei, declaring he no longer needs it. However, a group of aggressive cyclists led by Da Huan pursues Jian. In a bid to escape, Guei and Jian flee but soon find themselves cornered and severely beaten by Da Huan's gang. After the group leaves, one member remains to vandalize Guei's bike. In a moment of fury, Guei retaliates by striking his assailant with a brick, rendering him unconscious. With his battered bicycle resting on his shoulder, Guei walks away, alone and defiant.
