Through the ingenious arrangement of fate, Gu Yansheng, a modern elite lawyer, accidentally traveled to the Republic of China because of a mysterious wooden box engraved with strange symbols in his family's old house. On the streets of the Republic of China, he met Fu Qian, a progressive female student who shouldered the mission of saving the country. From identity misunderstanding to ideological collision, the two hearts gradually get closer in the turbulent years, and love quietly sprouts.
However, the power of time and space ruthlessly separated them. After Gu Yansheng returned to modern times, with the help of his friend Shen Yi, he frantically searched for a way to travel again. By chance, Fu Qian also traveled to modern times to meet him again. But before they could immerse themselves in joy, they discovered that a mysterious organization was manipulating time and space behind the scenes, trying to support reactionary forces in the Republic of China, change the direction of history, and realize its ambition to rule the world.
In order to protect the balance of time and space, Gu Yansheng and Fu Qian, under the guidance of their family elders, fought side by side with close friends such as Lin Yue and Shen Yi. They must not only avoid the pursuit of the mysterious organization, but also crack the secrets of time and space. In the process, they face the difficult choice of sacrificing love to save the world, or giving up their mission to protect each other. In the end, for the sake of great love, they chose to start a desperate showdown with the mysterious organization.
By chance, a mysterious phone call led them to an abandoned factory on the outskirts of the city, triggering a mysterious light and starting a journey through time and space. In the time and space of five years ago, they dealt with their younger selves and accidentally discovered a mysterious diary, but were transported to a war-torn era. Supporting each other in the cruel war, their feelings quietly warmed up, and they also got acquainted with a mysterious organization related to time and space travel.
