Late at night while taking a nap at his desk in the laboratory, modern young man Lu Yi accidentally traveled through time and transformed into a mountain demon from another world. Faced with unexpected changes, he accepted his fate calmly, walked out of the mountains and integrated into the villages below. He relied on his true nature to live in harmony with his neighbors, and gradually established a firm foothold in this world. By chance, he met a close confidant and a beautiful woman, and they became a fairy couple. In order to gain longevity and find a way to return home, the two embarked on a long journey to immortality hand in hand, devoted themselves to hard work, and finally achieved immortality. After that, they traveled all over the world, looking for cross-realm passages, and went through countless hardships and obstacles. Finally, they joined hands and returned to the homeland of the earth that they had been away from for a long time.
