Description："Promise" tells a touching story of a small person fulfilling his promise. Dou'er, the adopted daughter of Widow He Er, was admitted to the university. She was finally going to be together with her old lover Xu Ergua. However, a car accident destroyed the happiness they had been looking forward to for many years. Before she died, Widow He Er entrusted Dou'er to Xu Ergua and asked Xu Ergua to send Dou'er 500 yuan a month for living expenses. However, the first time Xu Ergua sent Dou'er living expenses, the money left by Widow He Er for him was stolen by a thief. In order to successfully collect living expenses for Dou'er, Xu Ergua made a living by picking up scraps and became friends with his neighbor Liu Shun. Dou'er gradually accepted Xu Ergua and fell in love with the handsome Liu Shun. However, an accident made Xu Ergua know Liu Shun's true identity...