By: Matthew Battles

Survival and storms, milliseconds at a time.

By: Joshua Glenn

Planetary Agent X (1965), by Mack Reynolds.

By: Peggy Nelson

Border crossings and cyborgs. And drawing on Mars.

By: Joshua Glenn

A scene from MADIGAN (1968).

By: Joshua Glenn

Madame X (1966), adapted by Michael Avallone from the 1966 movie.

By: Joshua Glenn

Nurse Lily and Mister X (1961), by Diane Frazer.

By: Joshua Glenn

Echo X (1962), by Ben Barzman.

By: Joshua Glenn

Perry Rhodan No. 16: Secret Barrier X (1972), by W.W. Shols.

By: Joshua Glenn

Sweet girl-graduates in their golden hair…

By: Peggy Nelson

If only these stones could sing.

By: Joshua Glenn

Utopia Minus X (1966), by Rex Gordon

By: Joshua Glenn

Athletic eggheads!

By: Joshua Glenn

Warrant for X (1945), by Philip MacDonald.

By: Matthew Battles

If books are architecture, then illustration can be street art, too.

By: Andrea Pitzer

A champion fighter who defied our sentimental unease.