Long Fei (Kim Ji-soo), Shang Yu (Jin Junmian), du Man (Jin Xizan) and Zhikong (Liu Junlie) are good friends from childhood to big, and they are very close to each other. After graduation, the four chose their own different future and embarked on their own journey of life. Shang Yu decided to join the army. Before leaving, several friends decided to go on a trip to release their youth. However, during the journey, the four accidentally met a strange woman in danger. Unable to sit idly by, the four extended a helping hand to the woman, who knew that they had been involved in trouble, became the suspect of the police investigation, and told the matter to their parents. Under the intervention of their relatives, the four young people began to be suspicious of each other, and the solid friendship gradually split.