Beginning with a statement saying these evil creatures are found only in imaginations, Sautter goes on to describe size, habitat, diet, life cycle, physical features, and behaviors as if they did exist.  Individual creatures in the book include: pixies, nixies, sirens, hags, boggarts, gremlins, goblins, hobgoblins, orcs, black orcs, and troglodytes.  Their sizes range from 6 inches to 7 feet tall.  Most live in dark places and have dark brown or green skin, have greedy appetites, and like practical jokes.  Some have been described in fairy tales or legends throughout the world.  A map indicates where pixies, hags, sirens, and goblins appear in literature.  A quiz (with answers), a glossary, additional books, internet sites, and a glossary are included.  This is surely to find an audience among readers of unexplained fantasies.