A long-extinct beetle appears in a physics lab. Four-and-a-half people and a dog are hurled 65 million years through time, to the Age of the Dinosaurs, and paleontologist Julian Whitney and his companions have only one chance for rescue.

Meanwhile in the lab, police chief Sharon Earles must solve the mystery of why half a body remains where five people had just been. Physicists try to determine what went wrong but can they fix the vault in time to retrieve the missing people--and do they want to?