Twenty-two-year-old Tatsuhiro Satou has been a hikikomori for nearly four years, shutting himself away from the outside world. In his isolation, he develops a belief in strange conspiracy theories, especially one claiming that a secret group called the Nihon Hikikomori Kyokai, or NHK, is behind his condition. As Tatsuhiro tries to break free from his self-imposed isolation and find purpose, he struggles with daily life and fears human contact. A chance meeting with the mysterious Misaki Nakahara offers hope, but also forces him to confront the one thing he fears most: society.