In the near future, Paris is divided into three social zones, and order is maintained by ALMA—an advanced artificial intelligence that has completely transformed the police force. When ALMA's creator is murdered, the investigation falls into the hands of an unlikely duo: Salia—an elite agent from Zone 2—and Zema, a bitter cop from the lowest, most excluded Zone 3. Despite everything that separates them, they must join forces to uncover a truth that could shake the very foundations of the system.