Quebec, 1980s. 10-year-old Jo, inspired by her cartoon heroine, dreams of saving her unhappy father. Surrounded by her three sisters and a busy mother, she finds an ally in Monsieur Roger, their gruff neighbor who hides …

一群生活在加拿大小镇的孩子，在寒假来临时，为了打发无聊的时间，小男孩卢克和刚到搬到镇子上的小女孩索菲亚约定了一场超大规模的雪仗。雪仗的规模不断升级，导致了意想不到的事故发生。