Takahata Shun’s day at high school begins just as boring as ever, but it doesn’t end that way. He and his classmates find themselves forced to play children’s games with deadly stakes. With no idea who is behind, the only thing Shun and other students can do is keep trying to win.

Ninako Kinoshita has never been in love until an encounter with the school’s most popular boy, Ren Ichinose, leads the two to befriending each other. Ren’s patient and kind personality is a far cry from his unapproachable idol status at school, and soon Ninako falls in love with him. However, she must cope with the fact that he already has a long-time girlfriend.

The movie is set in the near future, when the “ARK Project” has initiated a program to increase the quality of human life through the peaceful use of robots. Dr. Komyoji, the chief scientist on the project, has developed a process to create a robot with a figurative human “heart” through the installation of a “conscience circuit”, but his plans are violently opposed by researcher Gilbert Kanzaki. When Dr. Komyoji is killed in an apparent accident, his children Masaru and Mitsuko are targeted by mysterious forces within the ARK Project looking to gain control of the scientist’s research data. But the villains are opposed by Jiro, the android with a human conscience who fights for justice as the hero Kikaider.