Unearthing the Underworld reveals the hidden world of rocks - the secret-keepers of past environments, of changing climates and the pulse of life over billions of years. Even the most seemingly ordinary stone can tell us much about the history of this planet, opening vistas of ancient worlds of ice, raging floods, strange, unbreathable atmospheres and prehistoric worlds teeming with life. Remarkably, many types of rock owe their existence to living organisms, from the remains of dead animals to rotting ancient forests, or even the activity of fungi, bacteria and viruses. Anything but dull and uninteresting, rocks are intriguing portals that illuminate the secret underworld upon which we live.