In 1865, as Darwin's new theory of evolution begins to sweep aside old certainties, a young Jesuit priest and plant-hunter sets out into an unknown world. He is driven by twin passions: for science and for his faith. Travelling across the Eastern Steppes of Mongolia in the company of a Buddhist monk and a local horseman, Joseph's journey is fraught with danger, both physical and spiritual. But it is Namuunaa, the gifted shaman woman who saves his life, who offers a greater challenge: she will teach him what it is to love. A story of East meeting West and of a love that transcends culture, faith and, ultimately, tragedy, this is both a novel on an epic scale and an astonishingly intimate story.