In 1853, LEWIS -- a 14-year old orphan and self-taught mapmaker -- joins John Charles Fremont's last desperate expedition into the uncharted world. Denied the support of the US Government for whom he completed three expeditions that opened the West (and a fourth that led to the death of almost a third of his party), Fremont is grimly determined this time to redeem both his reputation and his chosen route for the nation's first transcontinental railroad. His well-publicized challenge is to prove -- despite his previous catastrophic failure - that the 38th parallel across the Rockies and the Sierra Nevada can be traveled in deepest winter.
In the course of the year that takes Lewis from his home in Boston to the Kansas territory where he first sees Indians and learns to ride and use a gun, and on into the merciless rigors of the west's barren deserts and snow-bound mountains, he comes to question his devotion to the man who has previously been the brightest star in his personal firmament. He also comes to understand that he himself can and must determine what his place will be in this world.
Simultaneously, in New Mexico, the 15-year old Adeline Carson is struggling to find her place in in-bred Taos. The half-Arapaho daughter of Kit Carson - the mountain man not incidentally made famous by Fremont - her Indian soul was cut out of her first at 3, when her mother died, and then even more so when she was brought East by her father and abandoned for almost a decade in a convent school in Missouri. Finally brought back west, she marries Louy Simmons -- a taciturn mountain man three times her age - but almost immediately falls in love with George Stilts, a passionate fiddler. When she heads for the gold rush country with her father and Simmons, the fiddler arranges to meet her there. Adeline decides, however, that it is more important for her to reclaim herself. On foot and alone and with only the vaguest memories of her childhood, she leaves the white man's world behind to seek the Arapaho lands.
Thus Lewis and Adeline are set on a continent-long trajectory toward each other. Between them lies a newly forged America seething with seduction, betrayal, casual violence and most savage nature. But stronger than any of these is love.