Det hemmelighedsfulde X

Benjamin Christensen

Lieutenant van Hauen

Karen Sandberg

Lieutenant van Hauren's Wife

Fritz Lamprecht

Rear Admiral van Hauen

Amanda Lund

Old Jane, nurse

Hermann Spiro

Count Spinelli

Svend Rindom

Teacher

Otto Reinwald

van Hauen's oldest son

Bjørn Spiro

Johnny, van Hauen's youngest søn

Robert Schmidt

Lawyer

Holger Rasmussen

Naval officer

Charles Løwaas

Naval officer

Finn Wennerwald

Naval officer