Ding Changwang (played by Roger Kwok) has been mentally retarded since childhood, and his intelligence has remained at the level of a 7-year-old. He was brought up by a single mother. Although Wang is not very intelligent, he is upright and very enthusiastic. He and his neighbor Afeng (played by Jessica Hsuan) grew up together and were childhood sweethearts. When Afeng went to school, Wang even gave all his savings to Afeng so that she could complete her studies in the United States with peace of mind. After returning from school, Afeng joined a local large group, the Zhong Group. In order to protect Afeng from being bullied by bad guys, Wang also joined the Zhong Group as a messenger. The boss of the Zhong Group (played by Paul Chun) is actually Wang's biological father, and his half-brother Zhong Zicong (played by Bosco Wong) is also a manager at Zhong. Wang's helpful and conscientious attitude towards life has infected many people around him, but can his 7-year-old intelligence level cope with the hypocrisy in the adult world?