Yuuichi selalu percaya persahabatan adalah segalanya—sampai ia dan empat temannya diculik dan dipaksa bermain "Tomodachi Game". Di ruang tertutup, mereka harus memilih: mengkhianati teman untuk uang, atau bertahan dan hancur bersama.

Yuichi Katakiri (Ryo Yoshizawa), Shiho Sawaragi (Rio Uchida), Tenji Mikasa (Yuki Yamada), Makoto Shibe (Shimon Okura) and Yutori Kokorogi (Nagi Nemoto) become involved in the "Tomodachi Game" to test money or friendship. They find that the person who attracted them to the "Tomodachi Game" is Tenji Mikasa. Maria Minase (Yuuka Ueno), who is a mysterious figure, takes part in the team which Yuichi Katagiri and Tenji Mikasa belong to.