Stewart Granger

as David Porter

Lex Barker

as Glenn Cassidy

Pierre Brice

as Agent Brice

Karin Dor

as Denise (Rio segment)

Walter Giller

as Karl (Vienna segment)

Johanna Matz

as Monique Carrar (Vienna segment)

Klaus Kinski

as Gomez (Rio segment)

Richard Münch

as Professor Alden (Frame story)

Peter Vogel

as Wendt, Suspected girls' killer (Frame story)

Pascale Petit

as Lotty (Vienna segment)

Agnès Spaak

as Nelly Small (Rio segment)

Herbert Fux

as Thug #2 (Vienna segment) (uncredited)

Harald Dietl

as Hans, Thug #1 (Vienna segment) (uncredited)

Raoul Retzer

as Doorman (Vienna segment) (uncredited)

Margaret Lee

as Agent Linda (Rome segment)

Roberto Miali

as Pessana (Rio segment)

Carla Calò

as Female boss (Rome segment)

Carmen G. Cervera

as Joana (Rio segment)

Allen Pinson

as Ray Runner (Rio segment)

Fregolente

as Harry Brenton (Rio segment)

Kim Camba

as Gigi (Rome segment) (unconfirmed)

Fortunato Arena

as Taxi driver (Rome segment) (uncredited)

Alberto Bonucci

as Professor (Rome segment) (uncredited)

Pietro Ceccarelli

as Gangster #2 (Rome segment) (uncredited)

Spartaco Conversi

as Gangster #4 (Rome segment) (uncredited)

Franco Daddi

as Gangster #3 (Rome segment) (uncredited)

Robert Favart

as Sergej (Vienna segment) (uncredited)

Michael Janisch

as Kurt Waldeck (Vienna segment) (uncredited)

José Lewgoy

as President (Rio segment) (uncredited)

Luciano Pigozzi

as Ivan (Rome segment) (uncredited)