This book investigates the validity of the asteroid impact hypothesis as the sole cause of the Cretaceous-Tertiary mass extinction. Charles Officer, a geophysicist and oceanographer, utilizes geological and paleontological data to challenge the prevailing consensus that a single extraterrestrial event triggered the collapse of dinosaur populations. He presents a framework that emphasizes terrestrial volcanic activity and gradual environmental shifts as more plausible drivers for the biological changes observed in the fossil record.

Experts acknowledge this work as a significant contribution to the debate surrounding mass extinction mechanisms, noting its rigorous focus on geological evidence. Readers frequently highlight the technical density of the prose, which demands a foundational understanding of earth sciences to fully appreciate the author's arguments.