When a paleoanthropologist mysteriously disappears in the remote upper regions of the Pamir Mountains in Tajikistan, two of his former students, once lovers and now competitors, set off in search of him. Along the way, they make an astounding discovery: a remnant band of Neanderthals, the ancient rivals to Homo sapiens, live on. The shocking find sparks a struggle that replays a conflict from thirty thousand years ago and delves into the heart of modern humanity.