At the time of the dynasty's collapse, Xie Queshan, burdened with the label of a “traitorous general,” pursues Nan Yi, a woman who accidentally steals a secret letter. To protect herself, Nan Yi is forced to stay in Xie's mansion, but unexpectedly witnesses the secrets hidden beneath his mask. Amidst the chaos of the times, the two go from tentative tests fueled by their own schemes to repeatedly joining hands on the brink of life and death. She sees a lonely guardian beneath his cold exterior, and he sees an inextinguishable firefly in her humble struggle for survival. Ultimately, they sail together on a solitary boat, facing the turbulent waves between family, country, and emotions.