For fans of Blake Crouch's Dark Matter and the survival horror of The Evil Within, bestselling author Jeremy Bates plunges a hapless man into a strange world within the subway tunnels beneath New York City, a subterranean limbo between reality and a nightmare where the only traces of humanity left are fear and the need to escape . . .

For high school teacher Clive Caldwell, it's a thankless and unremarkable life. Until a day that begins like any other. Against all logic, he falls through the solid wall of a school storeroom and awakens hours later to a familiar world gone strange.

On the streets of Manhattan, he's unseen and unheard by everyone, except a mysterious woman named Margot. With the unnerving whisper—I hope you're not afraid of the dark—she ushers Clive into a netherworld of labyrinthine tunnels beneath a city inhabited by a colony of others who have also inexplicably fallen through the cracks. A myriad of lost ones in a purgatory resigned to their godforsaken fates. Not ghosts. Not dead. Not alive.

But as Margot warns, whether it's here in The Tomb or venturing above ground, rules must be obeyed. Break them and there will be hell to pay. How can it be worse than this? In his need to understand what in the world is happening, Clive dares to find out. The only thing on his mind now is the dangerous desperation to escape. Because the truth that awaits him in this existence, as well as the real one he left behind, is beyond anything he could have imagined.