2018年3月，中国大陆的李嘉诚同学作为一名交换生，远赴台湾省台中市朝阳科技大学进行为期半年的学术交流。在这里，他遇见了台湾乡下长大的威志和在香港成长的子睿。刚刚来到台湾的嘉诚对于一切都有着特殊的防备之心。威志、子睿和嘉诚在慢慢组建三个人的小圈子时，逐渐发现，三位长不大的孩子都在被青春的尾巴所困扰着。热情的威志来到了城市，却怀念着乡下的这群小伙伴们；子睿暗恋着一位漂亮的老师，却不知如何是好；嘉诚在传统观念和台湾社会观念之中，寻找着自己的定位。三位孩子天天嘻嘻哈哈，从未向他人刻意提及过这些。可事实上，他们在玩闹中逐渐成长，逐渐为自己给出了一份答案。

In March 2018, li ka-shing from mainland China, as an exchange student, went to chaoyang university of science and technology in taichung, Taiwan province for academic exchange for half a year. Here, he met wei zhi, who grew up in rural Taiwan, and zi rui, who grew up in Hong Kong. Jiacheng, who has just arrived in Taiwan, has a special heart for everything. Weizhi, zirui and jiacheng gradually found that the three little children were troubled by the tail of youth. Enthusiastic wei zhi came to the city, but miss these small partners in the countryside; Zi rui secretly loved a beautiful teacher, but did not know how to be good; Jiacheng is looking for its position in the traditional concept and the concept of Taiwan society. The three children are always laughing and never deliberately mention these things to others. But in fact, they are growing up in play, and gradually give themselves an answer.