Eevee, an aspiring artist and daughter of Arizona's governor, and Danny, a reformed troublemaker who lives in foster care in his own world, join forces to correct a breach between parallel universes.

Four linked stories of discovery and survival begin with a Paleolithic-era girl who makes the first written signs, continue with Anna, who people call a witch, then a mad twentieth-century poet who watches the ocean knowing the horrors it hides, and concluding with an astronaut on the first spaceship from Earth sent to colonize another world.

Each of the Travelers returns home to learn the truth about their origins before being reunited for a final, ineveitable confrontation with Saint Dane, whose efforts to control Halla are destroying its very foundations.