For Cass, it's a place to escape the dull grind of her lonely life, a place where she can run its twisted laneways and live out her violent fantasies. For Detective Poe, it's a beat to walk, a dark, dangerous environment to hunt down his clues and get closer to whoever, or whatever, is haunting its streets. For Adlai, sitting drunk in a bar on the border between the River and the real world, it's a place to watch his creation transform from a theatre of heroism into, hopefully, something more vital.

While these three stories intertwine throughout the novel, one thread pulls them together: the nightmare vision walking the streets, a rogue musical virus that infects its users and feeds off their fears, growing stronger with each kill. Designed to take down the corporate powers of the Grid, a powerful governing entity on the banks of the River, this weapon has gone rogue, harvesting any user it comes across, threatening to collapse the entire structure of the River itself. Facing this threat, each character is altered, entangled with others looking for something real to hold onto in a world of technology and fantasy.