It has been fifteen years since the bloody New Year's Eve incident. Now, the world believes that the plan to destroy humanity using giant robots was orchestrated by the evil and terrifying Wise Men, while the masked mysterious figure who saved the world is worshipped as a deity by many. He issued a prophecy stating that humanity will soon face an apocalyptic disaster, and only those who believe in him will be saved. Snow replaced the missing Wise Men in raising his niece Megumi, who has grown into a smart and lively high school student. She knows it was actually her uncle and his companions who resolved the crisis. She is infuriated by the distorted history lessons at school. Buryudoni is being pursued after witnessing the Friend Party's attempt to silence witnesses. Megumi helps him hide, and a young police officer Chouno, moved by her actions, also lends a hand. With the nation under the control of the Friend Party, Megumi is seen as a heretic at school and sent to the Friend Party Training Grounds, a facility for brainwashing. Megumi and her classmate Ogawa Aki arrive there. Due to their excellent performance, they enter the Additional Stage, where the world from that year is recreated. Megumi finds herself in the science classroom of her elementary school, while Aki explores the rooftop platform of the teaching building, both seeking the truth about the Friend Party. Meanwhile, scattered members of the secret base are separately conducting underground resistance movements. Achi plans a jailbreak, Gisyou leads his team in covert operations, and Maruo awaits his opportunity. Amen discovers the real prophecy book after relentless investigation. Bacteriologist Yamane, the former transfer student Sada Kiyoshi, and childhood memories gradually resurface. In the end, the question remains: who is really the Friend? Can the impending crisis threatening this world be resolved?