Li Jianguo, an electric bicycle repairman, has worked diligently at Defa Repair Shop for eight years. While repairing a customer's bike one day, he discovers that the battery is not actually broken and only needs its connector fixed, saving the customer 1,200 yuan. Unexpectedly, instead of appreciating his honesty, the boss, Zhou Defa, pressures him to sign a parts-replacement performance assessment form! Furious, Li Jianguo walks away and joins Shengcheng Repair Shop. Facing exclusion from competitors, malicious price-cutting, and customer skepticism, he gradually wins back a good reputation through his genuine skills and secures major customer contracts. When his former boss finally comes knocking after his business takes a downturn, their positions have already completely reversed!