Describes what is known about the physical characteristics, behavior, habitat, and life cycle of this huge plant-eating dinosaur with the long neck and tail.

An uninvited dinner guest -- What is an Apatosaurus? -- What was the Jurassic Period? -- How do we know about Apatosaurus? -- How high could the dinosaur lift that head? -- What did Apatosaurus eat? -- Growing up and growing old.