Modern-day academic prodigy Mu Sang Sang returns from studying abroad and is about to get engaged to her childhood sweetheart when her soul crosses into another world. She becomes the principal consort of Xiao Qingyan, the Third Prince of Chishui.
Her husband already has someone he loves? She's not favored? Perfect. You two just enjoy your life together, and that's all that matters!
Qin Shi'an takes on the identity of Mu San and thrives outside the prince's residence. By chance, she meets Xiao Qingyan as Mu San. Their repeated encounters lead Xiao Qingyan to develop feelings for Mu San. After divorcing his wife for Mu San, he discovers that Mu San is actually Qin Shi'an, and is consumed with regret.
The daughter of the former Crown Prince of Xishu has been lying low in Chishui for years. She plans to kill Qin Shi'an, a princess sent to marry for peace, and ignite conflict between the two nations. Fortunately, the covert guard Feng Lan saves Qin Shi'an time and again, and the two fall secretly in love, eventually coming together. But fate has other plans: Feng Lan turns out to be the orphaned child of Xishu's Crown Prince. Torn between his younger sister and the woman he loves, Feng Lan ultimately dies saving Qin Shi'an.
Just as her heart is breaking, Lin Ye, who also crossed into this world, appears...
