All her life, Riley Bernard has felt like an outsider. Bullied and misused, she finds solace in her books and research. She comes to Yellowstone, hoping to learn about its ancient inhabitants, and unexpectedly overhears a strange tale about time travel from a couple of park rangers. When a mysterious box of artifacts arrives for her, she is thrust into field research beyond her wildest dreams.
Taken as a boy from the only family he knew, Cameahwait is thrown into an unknown world. The Sky People spoke of promises and tales that he was chosen for something great, yet they abandoned him to find his own way in a harsh and primitive land. When he finds a beautiful woman held prisoner by his enemies, he knows she may be the key to what he's sought for twelve long years.
Cam will stop at nothing to return Riley to her own time, even if it means facing those whom he turned his back on long ago. While searching for the ancient elders, the two embark on a journey of self-discovery and understanding of each other. When attraction turns to love, and Cam finally learns the truth about his past, he and Riley must make a choice to either follow their destinies, or allow an ancient evil to destroy the future of Yellowstone.