In a gleaming Tokyo City of the near future, investigator Ken Kanzaki carries one of the sharpest shooting records in the Metropolitan Police. His routine security assignment at a corporate gala shatters when phantom robots stage a devastating attack, leaving Ken and three other young men on death's door. Mysterious scientists at the police department perform experimental surgery on the survivors, integrating them with advanced mecha technology that transforms their bodies into living weapons. Now bonded with these armored suits, Ken and his unlikely companions, a street racer and a professional wrestler among them, become the Metropolitan Police's most powerful asset against an emerging robot threat. But their new existence comes with a cost. As they pilot their metal frames to protect the city from escalating mechanical attacks, questions surface about who orchestrated that fateful gala massacre and why the police were prepared with such experimental technology. Trust becomes complicated when you're not entirely human anymore. Ken must navigate both the physical demands of his transformation and the shadowy forces lurking behind the scenes.