Shen Jia Jia transmigrates into a book and into the spy character sent to infiltrate the villain's household, as his wife. The original character fails her task and is executed, so now she must ensure her character survives to the end of the book. Only then will the book be complete and she can go back to the real world. Gu Jiu Cheng, the villain, and her husband, is a cautious and domineering man who finds himself enamored of his new wife.