Reparto
Jack Mulhall
Chief Agent James Curtis
George Pembroke
Prof. Karl Schmidt
Kenneth Harlan
Agent Brown
Robert Frazer
John Oliver
Michael Vallon
Argus
Michael Whalen
Robert Norton
Anne Nagel
Nancy Fielding
Willy Castello
Otto
C. Montague Shaw
Franklin Prescott (uncredited)
Poppy Wilde
Restaurant Patron (uncredited)
William Bakewell
Tom Fielding
Constance Worth
Linda Pavlo
Hans Heinrich von Twardowski
Capt. Gemmler