Three hundred years after immortal fairy Jin Li seals Demon Lord Jie Chuan, a celestial beast named Jin Li accidentally frees him and is taken to the Demon Realm for her rare power. As enemies bound by fate, their hostility slowly turns into love—until a shocking truth about Jin Li's origin threatens to tear them apart and rewrite their destinies.

五年前的意外一夜，医女盛长歌与当朝皇帝谢景初相遇并诞下皇子，却对此毫不知情。谢景初五年来持续寻访当年女子，而盛长歌的婢女沈芸儿携其子冒名入宫，成为妃嫔。身份被窃取后，盛长歌在机缘下重返宫廷，与谢景初再遇，由此揭开层层谜团。随着真相逐步浮现，母子相认之路受阻于权力斗争与后宫倾轧，盛长歌在守护亲情与面对过往之间艰难抉择。谢景初在情感与帝王责任间挣扎，沈芸儿则为保地位不择手段，三人关系在阴谋与真情中不断拉扯，最终推动命运走向不可逆转的转折。