when chen yiduo was nine years old, his brother "bi laifu" suddenly airborne his family. lai fu, who lives in yiduo's home, is born with yiduo's "eight characters". the two not only faced each other at home, but also struggled continuously at school. at the same time, lai fu, who was just a newcomer, made friends with a group of friends who valued affection and friendship. these naughty boys often united to make trouble everywhere, causing headaches for adults. with the arrival of the college entrance examination, the children who grew up together went their own way, and lai fu and yiduo also began to face their work, love, and life. as time goes by 1998, the automobile industry has developed rapidly, and the old bicycle factories are no longer prosperous in the past. laifu feels that the bicycle factories are the memory of their generations. for this sentiment, he contracted the assembly workshop and attracted investment and renovated the production line. the brothers who grew up since childhood gathered together again, started a business again, and used new concepts to produce and manage the old "flying" bicycle factories, making the old "flying" bicycle factories younger again.