Twelve years of searching for a marriage, but once the situation is broken, it will be revealed. Watch repairman Guo Nian'an has been separated from his parents since he was a child, and his only keepsake is a mysterious copper gear. As an adult, he followed clues and went deep into dangerous situations, but unexpectedly discovered that his parents were anti-Japanese intelligence agents who had been lurking for many years. Because they had core information about the Japanese arsenal, they were secretly protected by the military commander for three years under the pretext of "imprisonment".
In troubled times, party barriers, family and country interests, and personal sentiments are intertwined. The charming and courageous daughter of the military commander Huang Li sacrificed her life to protect Guo Nian'an. Her father, Huang Zhiyuan, the director of the military commander, awakened after witnessing the brutality of the Japanese army and traitorous traitors. He abandoned the secret and led his men to fight against Japan. Relying on the precise craftsmanship and lock-picking skills he has developed in repairing watches, Guo Nian'an teamed up with his parents, Huang Li and underground party soldier Qiu Ju to decipher the secret code of the copper gears and attack the secret arsenal of the Japanese army.
From the life-and-death rescue at the Fuxing Flour Mill to the stealth raid at the bottom of the Huangpu River, everyone fought side by side in a hail of bullets: the thrill of delivering intelligence, the relief of family grudges, and the sacrifice of one's life for protection finally turned into a glimmer of light in a troubled world at the moment when the flames broke through the warehouse. When the gunfire stopped for a while, on the hilltop of the base, they looked in the direction of Shanghai and made a promise - when the Anti-Japanese War is victorious, they will open a stable watch repair shop, so that their family and country can be peaceful and their friendship will last forever. This is a story about finding relatives, awakening, resistance and hope. In an era when mountains and rivers are broken, the perseverance of small people illuminates the way forward for national salvation.
