Deliveryman Gu Sheng has a one-night stand with Shen Zhiyi, the eldest daughter of the Shen family. Shen Zhiyi asks Gu Sheng to enter into a fake marriage, but he refuses. Gu Sheng unlocks the Nine Dragon Lock to save Shen Zhiyi, revealing mysterious powers. Shen Zhiyi's grandfather falls seriously ill, and Gu Sheng comes to her rescue. Gu Sheng annuls his engagement at the Qiao Group and helps Qiao Qingya retain her position. Shen Zhiyi faces several crises, and Gu Sheng always comes to her aid, deepening their relationship. Gu Sheng investigates the truth behind the massacre of the Gu family to avenge his family, engaging in a fierce confrontation with "Buddha." Buddha uses Shen Zhiyi to threaten Gu Sheng, but Qiao Qingya rescues her. Gu Sheng ultimately defeats Buddha at his birthday banquet, avenging the Gu family and reuniting with Shen Zhiyi.
