"Dream" is a movie based on the theme of the Homeless World Cup. It tells the story of Hongdae (Park Seo-joon), a football player who is facing the biggest crisis in his career, and a special national team member who picks up a ball for the first time in his life to challenge the Homeless World Cup. IU plays the role of Lee So-min, a TV station PD who wants to succeed in making a documentary about the football team, so she hastily makes Hongdae a football coach. The Homeless World Cup is an international football tournament organized by the International Street Newspaper Network, and its characteristic is that all the participants are homeless.