Believing that the bodies must have been washed out of the city s sewers, Lieutenant Vincent D Agosta of the NYPD, FBI agent Aloysius X.L. Pendergast and anthropologist Dr Margo Green descend into a dark labyrinth of tunnels and subterranean galleries forgotten by those who walk the streets above. They will be led deep underground, far from the light, to confront their very worst fear…