Introduction: Monsters - essay by Isaac Asimov
Passengers - short story by Robert Silverberg
The Botticelli Horror - novelette by Lloyd Biggle, Jr.
The Shapes - novelette by J. H. Rosny aîné (trans. of Les Xipéhuz)
The Clone - short story by Theodore L. Thomas
The Men in the Walls - novella by William Tenn
The Doors of His Face, the Lamps of His Mouth - novelette by Roger Zelazny
Student Body - novelette by F. L. Wallace [as by Floyd L. Wallace]
Black Destroyer - novelette by A. E. van Vogt
Mother - novelette by Philip José Farmer
Exploration Team - novelette by Murray Leinster
All the Way Back - short story by Michael Shaara