The princess traveled through time for a year to help the prince build his kingdom and then left

A modern female military doctor traveled to ancient times with the mission of saving the Eastern Kingdom. She transformed into Qin Rubing, the legitimate daughter of the general who guarded the country, and married the dying King of Yan Chu Tiancheng. Chu Tiancheng is the chosen successor of the Eastern Kingdom. Relying on modern technology, Qin Rubing cured Chu Tiancheng's stubborn illness, who was originally expected to live for no more than three months. Afterwards, in the complicated and dangerous struggle for imperial power, Qin Rubing and Chu Tiancheng reached a cooperative relationship, trusted each other, fought side by side, and took every step carefully. Faced with the pursuit and interception of Prince Chu Tianxing, the frame-up of Concubine Qi, the jealousy and calculations of a group of noble ladies including the Crown Princess, the Crown Prince's concubine, and the illegitimate sister, as well as the mysterious failure of the time-travel mission...