The novel turns on a plot devised by Riley Steen, an associate of Burr's. Following on some discoveries Burr supposedly made, Steen has determined that if he can find a certain "chacmool", or mummy, to help channel the power of the Aztec god Tlaloc, and if he can create the perfect young virgin sacrifice to Tlaloc, a "new sun" will dawn in 1843. A new world will be created, and Steen believes he will be the temporal power in this world. To this end, he causes Jane Prescott, the daughter of a New York would-be journalist named Archie Prescott, to be burned horribly. He captures Jane in the aftermath of the fire, in which Archie believes she died along with his wife. Some years later, Jane escapes back to New York, to haunt an unbelieving Archie with her claim that she is his long-lost still-living daughter. Meanwhile, Steen finally manages to locate the chacmool, who is found in Mammoth Cave by a slave named Stephen Bishop.

The main plot revolves around Archie's semi-coincidental involvement with the chacmool, which Steen has temporarily stashed in P.T. Barnum's American Museum. (In time-honored secret/alternate history tradition, Irvine throws in reference to a few well-known historical characters, most notably his own ancestor Barnum, as well as a cute cameo from Edgar Allan Poe.) Archie stumbles upon the chacmool awakening to its power, and after nearly dying on a couple of occasions, he finds himself somehow linked to it. Finally he believes in Jane's claim that she is his daughter, but too late: she is under the chacmool's power, kidnapped again and taken to Mammoth Cave to be a willing sacrifice. Archie must travel halfway across America to find his daughter, and to reconcile his own desires with those of Stephen Bishop, Jane, and two old gods. Meanwhile Stephen must weigh Tlaloc's promise of freedom from slavery with his own sense of morality; while a variety of dead people and other gods also try to interfere.

The story is exciting enough, and the ending is well-done and satisfying. But along the way I was unconvinced on a couple of grounds. Most problematic was the motivations of various characters, who seemed to do the plot's bidding against all good sense. Likewise, all the characters leaped too rapidly, to my mind, to belief in some truly weird happenings. Finally, I never really engaged emotionally, or mythically, with the old gods Irvine describes. Pure and simply, they and their powers did not resonate with me. So the novel was somewhat interesting, but not wholly satisfying. Nonetheless, it's a promising debut for an author I will continue to watch closely.