Beginning in the vast North American Boreal Forest that stretches through Canada, and roving across the continent, from the Northern Sierra to Alabama's Paint Rock Forest, Tony Hiss sets out on a journey to take stock of the "superorganism" that is the earth—its land, its elements, its plants and animals, its greatest threats-and what we can do to keep it, and ourselves, alive. Hiss not only invites us to understand the scope and gravity of the problems we face, but also makes the case for why protecting half the land is the way to fix those problems. He highlights the important work of the many groups already involved in this fight and he introduces us to the engineers, geologists, biologists, botanists, oceanographers, ecologists, and other "Half Earthers" like Hiss himself who are allied in their dedication to the unifying, essential cause of saving our own planet from ourselves.