11岁的男孩小杰(于坤杰 饰)自幼便和经营公路旅店的大舅(孙心福 饰)一家共同生活。小杰为了完成学校作业——制作一副“大海”主题剪贴画,渴望得到一本《海洋百科》图书。表姐(李蔓瑄 饰)原本答应为弟弟买书,然而大舅突遭车祸,真凶拒不赔偿,全家陷入麻烦之中。 小杰不忍为家人再添烦忧,决心通过自己努力得到图书。他穿行在城镇和乡村之间,游荡在现实与幻想边缘,少年与海的秘密翻涌浮现……Eleven-year-old Xiaojie is a troublemaker who loves the sea. He lives with his uncle and his angelic daughter, who run a restaurant together. One day, Xiaojie has to prepare for a presentation on the sea for school. He desperately needs an encyclopedia, but financial difficulties at home prevent his wish from coming true. The situation at home gets worse after his uncle gets hurt in a car accident. His uncle and the villagers try to lead Xiaojie, who witnesses the car accident, to make a false statement for the settlement money. When he refuses, his cousin asks him to make a false testimony, promising to buy him an encyclopedia on marine life. However, when Xiaojie heads to the police station to make a statement, he learns a shocking secret about his parents. In the frustrating world of adults, Xiaojie chooses to do the only thing he can do. Over the Sea is a poignant film that evokes empathy and compassion by providing a look into the deep-seated wounds and thoughts of a boy who seems bright and carefree on the outside, through his unique world view that drifts between reality and fantasy. An outstanding performance of the young actor who plays the role of Xiaojie makes it difficult for the viewers to tear their eyes away from the screen until the very end.