During the height of summer, watermelon trader Zhou Qiang predicts an approaching typhoon and offers to buy the villagers' watermelons for cash at a low price. Instead of appreciating his offer, the villagers accuse him of being greedy. An internet celebrity seizes the opportunity to enter the village, promising them much higher prices and stirring them up to break their agreements. Zhou Qiang decisively turns to buying watermelons from a neighboring village instead. When the typhoon and torrential rain arrive, all the watermelons in the village are ruined and rotten. The influencer's livestream sales campaign collapses, payments are frozen, and the actual purchase price turns out to be extremely low. The influencer then flees with the money. Full of regret, the villagers desperately beg Zhou Qiang for help. He agrees to buy their damaged watermelons at a low price, but sets strict rules, teaching everyone through bitter experience that business requires honoring contracts and respecting the forces of nature.