In 2089, humanity created sentient AI. By 2090, the world was ending. In desperation, scientists engineered the Cell Circuits—genetically perfected super-soldiers capable of defeating the machines. The war ended, but the Cells endured, living centuries beyond their purpose. In 2478, Eurus, a stoic and deadly Cell, operates as a mercenary in the Martian megacity of Papülonis. His latest job—investigating a mutant infestation—uncovers an illegal attempt to resurrect Cell technology. It also draws him into the orbit of Kalopsia Chromo, a missing heiress with no idea she was designed to birth the next generation of super-soldiers.