An entire senior-year high school class accidentally travels to the world of cultivation during evening self-study, while only Lin Yue remains on Earth for three days before entering this world as well. His former deskmate has already become a sect master at the Great Ascension Realm, and his classmates have all become powerful figures across the Three Realms. After being swept into another world by a world stone for 300 years, the reclusive classmate Li Ming operates behind the scenes, plotting to seize the complete timeline of Earth within Lin Yue and rewrite his own origins. Xia Yao, Jiang Chi, and the others protect Lin Yue and uncover the truth behind their time travel. In the end, Li Ming and Xia Yao sacrifice themselves to forge a passage between the two worlds, allowing the entire class to return home to visit their families every year. With an osmanthus tree preserving their bonds, the story of these young friends continues across two worlds.