Shen Aojun holds the core technology of controlled nuclear fusion, and hires top mercenary Lin Xiao to personally protect his daughter Jiang Zhiruo, who studies at Nancheng University. Jiang Zhiruo is initially resistant in every possible way, but after experiencing multiple crises, she sees through Lin Xiao's toughness and reliability. Betrayed by her best friend and pressured into marriage and assassinated by a rich second-generation heir, she relies entirely on Lin Xiao to step forward and resolve it. Following the clues, Lin Xiao investigates and finds the real mastermind, slays the mastermind behind the scenes, and protects the technology.