Lei Dong from Leijiakao is the last generation of mountain watcher. A misunderstanding makes him take a solemn oath in public to prepare all wedding rituals within three months and grandly marry Tong Xing. On his way into the mountains, he slips and falls into the water, accidentally gaining an opportunity and finding a clue to his father's disappearance. Since then, relying on his forestry skills and starting from wild mushrooms and mountain goods, he gains a firm foothold in the town. Facing those who want to destroy the mountain and mine, he protects the mountain forests and the livelihood of the villagers. When the three-month period expires, he fulfills his promise and brings his bride home.