Persecution sends these genetically altered people fleeing to their sanctuary world, but a shipboard disaster exposes High Commander Brennen Caldwell to fatal radiation.

Elsewhere, wrongfully imprisoned Sentinel Jorah Caldwell receives a supernatural visitor, who hails Jorah as Boh-Dabar, the prophesied Word to Come. Meanwhile, a mysterious stranger arrives at the sanctuary world, also claiming to be Boh-Dabar.

Soon, a tangle of interstellar incidents threatens the Sentinel kindred's very existence. And no one-anywhere-has anticipated the events that will shake the interstellar Federacy.