Writer Jack Hitt discovers that the world of dinosaurs is a man-made creation, a simulated world that may or may not accurately reflect what happened on earth 100 million years ago. Talking with dinosaur experts like Jack Horner (whose work was the basis of much of the film Jurassic Park), Hitt finds that most of what you think you know about dinosaurs is probably wrong, and that Americans' ideas about dinosaurs go through "fashions" that reflect the national mood: We believed dinosaurs were more aggressive when we were on the brink of World Wars One and Two.