Mo Liancheng, the 8th prince of Dongyue, is forced to marry Qu Taner, who loves his elder brother, Mo Yihuai. After a failed suicide attempt, Qu Taner wakes up with another soul inside her, causing her personality to shift. As Mo Liancheng grows suspicious, he falls for Xiao Tan, the modern soul, while she tries to return to her world.

Delivery worker Xiaoxue meets Song Yuxian, the daughter of the Song Group, and discovers they look identical. The two become close friends, each admiring the other's life. Meanwhile, Song Yuxian's husband, Xia Qingyang, the CEO of the Song Group, seems to know more about Xiaoxue than he reveals.