WAVE, a self-driving car developed by Akatsuki Motors and nearing practical use, suddenly stops during a public-road test, killing the head of advanced technology, who had caused a power-harassment scandal. As threatening emails arrive from someone claiming to be the victim, the Metropolitan Police Department's cybercrime division launches the world's first investigation using an AI named Maris.

A technology mystery in which the police cybercrime division uses AI to investigate an inexplicable fatal accident involving a self-driving car.