"The disappearance of the dinosaurs at the end of the Cretaceous period posed one of the greatest, long-standing scientific mysteries. This three-act film tells the story of the extraordinary detective work that solved it. Shot on location in Italy, Spain, Texas, Colorado, and North Dakota, the film traces the uncovering of key clues that led to the stunning discovery that an asteroid struck the Earth 66 million years ago, triggering a mass extinction of animals, plants, and even microorganisms. ... Representing a rare instance with which many different scientific disciplines--geology, physics, biology, chemistry, paleontology--contributed to a revolutionary theory, the film is intended for students in all science classes"--Container excerpt. An earth-shattering hypothesis -- Following the trail of evidence -- Mass extinction and recovery.