In Republican-era China, orphan Lin Chuning believes her best friend Xiaorou was killed by the wealthy playboy Lu Siyan. Bent on revenge, she infiltrates the Lu family by impersonating his long-lost "twin sister," posing as the missing heiress to get close to him and exact vengeance.

Doctor Chu Jinghong accidentally entered a different world and became the princess of Northern Chu Kingdom. In order to return to the original world as soon as possible, she must face all kinds of difficulties. In the process, she falls in love with the war King Yu Longyuan.