Why did the dinosaurs and two-thirds of all living species vanish from the face of the Earth sixty-five million years ago? Throughout the history of life a small number of catastrophic events have caused mass extinction, and changed the path of evolution forever. Two main theories have emerged to account for these dramatic events: asteroid impact, and massive volcanic eruptions, both leading to nuclear-like winter. In recent years, the impact hypothesis has gained precedence, but Vincent Courtillot suggests that cataclysmic volcanic activity can be linked not only to the K-T mass extinction, but to most of the main mass extinction events in the history of the earth. Courtillot's book, first published in 1999, debunks some of the myths surrounding one of the most controversial arguments in science. This story will fascinate everyone interested in the history of life and death on our planet.