After Chinese reform and opening-up in 1978, family Chen, Lin and Pan who live in Beijing have their own life track. Chen Huan and Lin Pingping were admitted to colleges since the college entrance exam was resumed and got married. Under the influence of the environment, Pingping went to America for studying abroad, but Huan insisted his research in China, which caused their relationship gap. And other children of the three families also had different life path. During the past 40 years, they experienced their lives through hopes and hardships. And the great changes of times left them impression deeply.