meneer x thumb

Meneer [Mister] X (c. 1928), by Valentine Williams.

x contra

Mr. X contra Scotland Yard (1949), by Martin Porlock.

dutch x

De Afschuwelijke X (c. 1946), by R. Poupon.

lee x thumb

Christopher Lee’s ‘X’ Certificate (1975)

hilgendorf x thumb

Organization X (1954), by Hermann Hilgendorff.

denmark x thumb

Mr. X: King of the Underworld (1942), by Jack Lester.

lab x thumb

Laboratory X

nebula x

Nebula X

x people thumb

The “X” People

assignment x thumb

Assignment X

minus x thumb

Minus X

planet x thumb

Planet X

harris-x-thumb

Let X Be Excitement (1969), by Christie Harris.

duncan-x-thumb

Dangerous Mr. X (1929), by Francis Duncan.

roberts-x

A collector’s guide!

gallunx2

People Minus X (1958), by Raymond Z. Gallun.

robx

The Face of X (1960), by Lionel Roberts.

horlx

Virus X (1945), by Sydney Horler.

Screen shot 2010-08-23 at 6.30.34 PM

Commando X (1967), by Poke Runyon.

adamx

The Man from Planet X No. 2: Tiger by the Tail (1975), by Hunter Adams.

sellx

The Power of X (1968), by Arthur Sellings.

reyn-x

Planetary Agent X (1965), by Mack Reynolds.

avallone-x

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

frazer-x

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