Dafu (Zhang Wen), who just turned 21, is an autistic patient. His father Wang Xincheng (Jet Li) raised Dafu alone after his wife died. Now Wang Xincheng suffers from liver cancer and feels that he doesn't have much time left. Although Aunt Chai (Zhu Yuanyuan), who runs a small shop downstairs, often gives selfless help to the father and son, Wang Xincheng is still concerned about how to arrange Dafu's future. He even has the idea of dying with his son. Wang Xincheng tried to send Dafu back to the special education school, but a series of rejections from the school and the welfare home made him feel lost. Moreover, in Dafu's world, water is his best friend. This autistic patient who can swim like a dolphin cannot leave the aquarium. In the aquarium, Dafu met the kind acrobatic woman Lingling (Gui Lunmei), and Wang Xincheng was eager to teach Dafu the skills of survival. He didn't have much time left...