Contents: • Introduction by August Derleth • Primitives by August Derleth • From a Private Mad-House by Humphrey Repton • Missing One's Coach: An Anachronism by Anonymous • Tale of a Chemist by Anonymous • The Last American by J.A. Mitchell • Mid-Period Pieces by August Derleth • Infinity Zero by Donald Wandrei • Frankenstein - Unlimited by H.A. Highstone • Open, Sesame! by August Derleth [as by Stephen Grendon ] • Tepondicon by Carl Jacobi • The Fear Planet by Robert Bloch • The Contemporary Scene by August Derleth • De Profundis by Murray Leinster • Invasion by Frank Belknap Long • Dear Pen Pal A.E. van Vogt (aka Letter from the Stars) • Time to Rest John Wyndham [as by John Beynon Harris ] • An Ounce of Prevention by Paul A. Carter [as by Paul Carter ] • The Song of the Pewee by August Derleth [as by Stephen Grendon ] • And Lo! The Bird by Nelson S. Bond [as by Nelson Bond ] • The One Who Waits by Ray Bradbury • Vignettes of Tomorrow by Ray Bradbury • Holiday by Ray Bradbury • The Man Who Rode the Saucer by August Derleth [as by Kenyon Holmes ] • Later Than You Think by Fritz Leiber