
THIS WOMAN is the most thrilling act of espionage you've ever seen! She holds the key to "Matchless" - a spy plot as flawless as her beauty - as reckless as her body!
A secret agent possesses a ring that makes him invisible for a short time, once every 10 hours. He is in pursuit of an evil criminal mastermind but, at the same time, must evade an enemy agent who also wants the ring.

Patrick O'Neal
Perry 'Matchless' Liston

Ira von Fürstenberg
Arabella

Donald Pleasence
Gregori Andreanu

Henry Silva
Hank Norris

Nicoletta Machiavelli
Tipsy

Howard St. John
General Shapiro

Sorrell Booke
Colonel Coolpepper
Tiziano Cortini
Hogdon (as Lewis Jordan)
Elisabetta Wu
O-Lan (as Elisabeth Wu)

Eddra Gale

Ennio Antonelli

Geoffrey Copleston
Gianluigi Crescenzi

Alfredo Martinelli

Massimo Ciprari