Satan's greatest trick? Convincing the world he didn't exist. Here, at the bottom of the ocean, at the bottom of the earth, Dr. Randolph Stein is about to plumb the depths of his very soul, as he discovers that some things can't be explained by facts, or science or reason. Some things do defy explanation. Something does live down here in the black water of the Marianes Trench, and it wants to show Stein its secret, whether he wants to see it or not.