In the apocalypse, Tang Zhiwan is betrayed by her teammates and unexpectedly transmigrates into the Great Yun Kingdom, becoming the legitimate daughter of a marquis who is destined to marry the dying Regent, Zhan Wenguang, as a bride meant to bring him good fortune—and to be buried alive alongside him if he dies. Using her portable space and miraculous spiritual spring medicines, she saves Zhan Wenguang's life, and the two unexpectedly consummate their marriage. With the Regent's protection, she fights back against her marquis family's cruelty and schemes, outsmarts the malicious Emperor and Empress, and devotes herself to protecting her long-suffering mother. In this ancient world, she finds a sweet romance while carefully rewriting both her own destiny and her mother's.