The vegetarian diet is praised for being sustainable and animal-friendly, but after 20 years of being a vegan, Lierre Keith has changed her opinion. Contravening popular opinion, she bravely argues that agriculture is a relentless assault against the planet. In service to annual grains, humans have devastated prairies and forests, driven countless species extinct, altered the climate, and destroyed the topsoil - the basis of growth and life itself.