Xue Yuke, the Great Xia's ace bodyguard known as the King of Hell, conceals his identity and works as a food delivery driver, only to discover that his fiancée, Su Man, has betrayed him. Just then, his younger sister is kidnapped by human traffickers, forcing him to come out of hiding and rescue her. Along the way, he meets Zhang Qingyao, the legitimate daughter of the Zhang family. After destroying the human traffickers' hideout, he discovers that the mastermind is Duan Mingyuan, his brother-in-law who caused his elder sister's death. Xue Yuke goes undercover to gather evidence of his crimes and ultimately captures Duan Mingyuan, avenging his sister.