Summer Wars

During the summer vacation of his sophomore year in high school, Kenji Koiso, a timid genius mathematician, agrees to work part-time for his senior crush, Natsuki Shinohara. The two travel to Natsuki's family home in Nagano, only to discover it is inhabited by a large clan of twenty-seven people. The matriarch, Grandma Sakae, heads the Jinnochi family, which traces its lineage back to the Sengoku period. Relatives from across the country have gathered to celebrate Sakae's 90th birthday on August 1, 2010. At this moment, Natsuki suddenly asks Kenji to pretend to be her fiancé. Due to Sakae's insistence, Kenji is forced to stay in the countryside for several more days. Overwhelmed by the hospitality of Natsuki's relatives, he struggles under the pressure of playing the role of the fiancé. Then, one night, he receives a text message containing mysterious numbers. With his mathematical aptitude, Kenji becomes fascinated by the code and attempts to decipher it... The next day, the world undergoes a drastic change. A mysterious figure who deceived Kenji plunges the world into chaos... "Our family will take responsibility for everything!" Under Sakae's command, Kenji, Natsuki, and the members of the Jinnochi family unite to combat the global crisis.