Liu Yang, a front-line power worker, stays steadfast on the front line of urban power supply and emergency repair. During a repair work, because he insisted on safety standards and refused to violate operating regulations, he was unreasonably fined six thousand yuan and also faced criticism from multiple parties. On the very night the penalty was issued, the city's main power grid suffered a major sudden breakdown, causing a large-scale blackout across the entire city. At this critical moment, everyone was helpless, leaving only Liu Yang, who was familiar with the line hazards, to accept the mission in time of crisis. Braving pressure, he went against the flow overnight to make repairs, risked danger to troubleshoot faults, raced against time to restore power, guarded the lights of thousands of households with his professionalism and perseverance, and also made everyone see the responsibility and grievances of front-line power workers.