In the 14th year of Tianbao in the Tang Dynasty, Li Shande, a small official in Chang'an City, suddenly received a task: Before the birthday of the imperial concubine, fresh lychees should be shipped from Lingnan. Lychee changes its color in one day, its fragrance in two days, and its taste in three days, and Lingnan is more than 5,000 km away from Chang'an, and it is an impossible task. But for the sake of his family, Li Shande is determined to give it a shot: "Even if I fail, I want to know how far I am from the finish line.