The government has established a military program, the , wherein fifty randomly selected classes of third-year junior high school students are kidnapped, dropped into a remote location, and forced to kill one another until only one student of each class remains. Ostensibly, it is to help the government and its military research survival skills and battle readiness – in actuality, it is meant to instill terror and distrust in all of Japan's citizens to curb any attempts at rebellion, by showcasing the government's power and ability to target citizen's families and preying on the fear of being killed by a friend.