Henghis Hapthorn is the foremost penetrator of mysteries and uncoverer of secrets in a decadent, far-future Old Earth, one age before Jack Vance's Dying Earth. A superb rationalist, he has long disdained the notion that the universe has an alternative organizing principle: magic. But now a new age is dawning, overturning the very foundations of Hapthorn's existence, and he must struggle to survive in a world where all the rules are changing.

With Old Earth on the cusp of the transition to a universe that operates on the principles of sympathetic association (or, to be vulgar, magic), Hapthorn is thrust forward through time into the first centuries of the new order. He becomes a pawn in a contest among five wizards, while an unknown entity with the power to frighten demons keeps bellowing through all the nine planes of existence: "Bring me Apthorn!"