At the center: Luna Stone, twenty-eight, on the mend from a nervous breakdown, traveling west with her beautiful, self-involved boyfriend. Their plan is to marry in Reno, but when the moment of decision comes, Luna takes off for the High Sierra, camping out near the spot where long ago the Donner Party starved and died. There she has three unexpected encounters: She becomes profoundly attached to a runaway boy, Sam, an escapee from a child prostitution ring whom she has caught stealing her food. She establishes a cautious understanding with a charming, shy would-be minister, in despair because he's going deaf. And she is visited by the ghost of Tamsen Donner - an outsize, insistent presence - who seems to have something important to say to her about men and the nature of love. As Luna gradually wins the boy's trust, the minister, Paul, begins to overcome Luna's resistance to making a new emotional connection, and together the three start wandering, sightseeing around Reno. Until one day Luna is minutes too late to keep young Sam from being snatched again by his exploiters. And a breathtaking chase is set in motion that will change the world in undreamed-of ways for all of them.