Summer Wars is a 2009 Japanese animated science fiction film directed by Mamoru Hosoda and produced by Madhouse. The story follows Kenji Koiso, a high school student and math genius, who is invited by his crush, Natsuki Shinohara, to her family's home for a summer celebration. However, the virtual world OZ, which Kenji accidentally helps hack into, threatens to wreak havoc on the real world, and he must join forces with Natsuki's family to stop the impending disaster.