On screen
Cast
18 credited performers
Richard O'Sullivan
Roger Court
Alida Valli
Roberta Gleukovitch
Eduardo Ciannelli
Dr. Vivaldi
Trevor Howard
Major Roger Court
Richard Basehart
Joe Hamstringer
Stephen Murray
British Consul in Venice
Arnoldo Foà
Commissioner
Guido Celano
Chief Constable
Helen Goss
Undetermined Role
Artwork unavailable
Giorgio Costantini
Pescovitch
Artwork unavailable
Angelo Cecchelin
Luza
Artwork unavailable
Nino Vechina
First Killer
Artwork unavailable
Armando Papette
Second Killer
Artwork unavailable
Giovanni Karuz
Third Killer
Artwork unavailable
Joan Butterfield
Mrs. Harrington
Artwork unavailable
Alessandro Paulon
Morgan
Artwork unavailable
Remington Olmsted
Ramondo
Artwork unavailable
Jacopo Tecchi
Character not listed