This book describes how alien monsters have been imagined in books and movies and examines real creatures in nature that resemble or may have served as inspiration for them.

Contrasts the monster-creating escapades of mad scientists such as Frankenstein, Moreau, and Jekyll with the methods used by real scientists who try to help, not hurt, the world.

This book discusses were-creatures, monsters that change from one entity into another, such as werewolves and cat people, including some scientific explanations for these beasts.