Having learned the shocking truth behind a plot to cast the world into unimaginable darkness, Miskatonic University professor Oliver Grayson and his team of unlikely allies must arm themselves with deadly weapons, powerful eldritch artifacts, and the most potent tool an investigator can wield: knowledge. The stage is set for one ultimate, heart-stopping race to save mankind! Dweller in the Deep is the final installment of The Dark Waters Trilogy by award-winning author Graham McNeill, and it concludes the harrowing story begun in Ghouls of the Miskatonic and continued in Bones of the Yopasi.