Sam Morgan, once a young runaway from Philadelphia, now a seasoned fur trapper and mountain man, faces the most daunting task of his adventuresome life. It is 1827 and he, together with the trapping brigade commanded by Jedediah Smith, has been expelled from Mexican California. To his unending sorrow, Meadowlark, Sam's beloved Indian wife, has died in childbirth and he has been forced to abandon his infant daughter, Esperanza. Now, Sam is determined to reclaim his baby and take her to Meadowlark's village on the Wind River of Wyoming. In Santa Fe, Sam meets a beautiful widow known as Dona Paloma and the two become lovers. Then, after the herd of horses belonging to Sam and his companions are sold for a healthy profit, he returns to California to reunite with his daughter only to learn she has been taken captive in an Indian raid. Sam's desperate mission to rescue his daughter, their escape in a frail craft down a rampaging river, and their long trek to Santa Fe, is a harrowing tale told by a master of the historical novel.