Feng Dali (played by Chen Zhipeng), Gu Xiang (played by Luo Liqun), Xiao Zhiyuan (played by Huang Jue) and Wu Xiaobei (played by Liu Chao) used to be good brothers who could talk about anything. However, as time went by, the contact between the four people who entered society gradually became less and less. One day, Xiao Zhiyuan called the other three and told them that he was about to hold a wedding in Lijiang, hoping that the three of them would come to support him. So, the three of them set off on a journey to beautiful Yunnan. Feng Dali is a divorce lawyer. After seeing too many relationships break up and get back together, he gradually lost confidence in marriage. But at this time, his girlfriend Jiang Xiaoyu (played by He Lin) told Feng Dali that she was pregnant, which made Feng Dali not know how to choose. After arriving in Lijiang, what awaited them was not a grand wedding, but a letter written by Xiao Zhiyuan to the three of them. In the letter, Xiao Zhiyuan assigned three tasks to the three of them, hoping that they could complete them for him.