An ancient Hopi prophecy ... the end of the Fourth World ... a mysterious ruin ... and a window between worlds.

Anthropologist Will Lansa grew up as a privileged child in Aspen, Colorado, but spent summers on the Hopi reservation, where his father was chief of police. Now Lansa grudgingly returns to his roots on the reservation after receiving a baffling message from Vina, his aged grandmother.

Vina sends him on the quest of a lifetime to find Pahana, the Hopi's returned savior, and locate the missing part of the Hopi's sacred tablet. But Will soon encounters strange and disturbing events, and becomes a suspect in a murder. Pursued by FBI agent Ellie Fletcher, the two find themselves literally lost in another world, unable to get home, and hunted by Maasau'u, the manifestation of the god of death and guardian of the Underworld.