A country ruled by a fictional government. 35 students from the same class, all high school seniors, are forced to participate in "The Program," a killing game conducted by the government. The participants consist of 19 boys and 16 girls, totaling 35. The stage is a deserted island isolated from the outside world. The goal of the game is for students to kill each other until only one survivor remains. Each participant is randomly assigned one weapon. A special collar is attached to each participant's neck, which will explode if they violate the rules or if certain conditions are met. Forbidden zones are established on the island, and the playable area shrinks as time passes. After the game begins, the 35 students are gathered in a classroom of an abandoned school, given duffel bags containing weapons, food, and water, and sent out one by one in order of their student numbers.

Assigned Weapons Each of the 35 participants is distributed one random weapon. There is a significant disparity in weapon types, ranging from powerful armaments to items entirely unsuitable for combat. Victory or defeat is not determined solely by the strength of the weapon.

No. 01 Ren Asakura No. 02 Asahi Kamiya Male. Popular in class. Social and courageous. Will choose to kill depending on the situation. No. 03 Reo Kurosaki Male. Leader of a delinquent group. No. 04 Naoya Mizuno Male. Yui Shiraishi's boyfriend. Kind and sincere. No. 05 Koichi Kiryu Male. Captain of the soccer club. Strong sense of responsibility and cares for his teammates. No. 06 Minato Tachibana Male. A reliable, big-brother figure. No. 07 Yuma Mikami Male. The class mood maker. Gets along with everyone. No. 08 Iori Sakakibara Male. An intellectual with excellent grades. Calm, collected, and rational. No. 09 Saku Mikage Male. A quiet hacker. No. 10 Akiya Mihara Male. Guest's boyfriend. No. 11 Koichi Soma Male. Quiet and inconspicuous. Has the potential to change when cornered. No. 12 Koh Toma Male. Guest's childhood friend. No. 13 Kazuki Todo Male. No. 2 of the delinquent group. Short-tempered and aggressive. Strongly trusts Reo Kurosaki. No. 14 Shun Miyamoto Male. Strong sense of justice. Aims to destroy the Program itself and stop the killing. No. 15 Kano Hayakawa Male. Hard worker. Hates losing and will take any necessary means to survive. No. 16 Kanata Yuki Male. Gentle and kind. Mutually in love with Natsuki Aizawa. No. 17 Tomoya Seto Male. A jokester and class mood maker. Cowardly and unable to kill. No. 18 Hayate Onodera Male. A silent lone wolf. Prepared to fight if necessary. No. 20 Mizuki Ichinose Female. No. 21 Riko Sakurai Female. Center of the gyaru group. Strong-willed and proactive. No. 22 Saki Mito Female. Cheerful and social. Fundamentally refuses to kill. No. 23 Naomi Kurokawa Female. Cool-headed. Will choose to kill if it means her own survival. No. 24 Yui Shiraishi Female. Naoya Mizuno's girlfriend. Kind and considerate. No. 25 Mao Takahashi Female. Athletic and competitive. No. 26 Reina Kanzaki Female. Calm and sharp-witted. No. 27 Kanon Koizumi Female. Quiet and cowardly. No. 28 Chihiro Fujiwara Female. Quiet and reserved. No. 29 Anna Morishita Female. Cheerful and helpful. No. 30 Natsuki Aizawa Female. Serious and kind. Mutually in love with Kanata Yuki. No. 31 Aoi Nishikawa Female. Has a calm personality. No. 32 Momoka Endo Female. Has a bright and flashy personality. No. 33 Rio Shinohara Female. Quiet. No. 34 Miyu Hojo Female. A refined young lady. Member of the tea ceremony club. No. 35 Akari Naruse Female. Member of the literature club.