A German submarine is sent to the Orkney Isles in 1917 to sink the British fleet.
Conrad Veidt
Captain Ernst Hardt
Sebastian Shaw
Ashington
Valerie Hobson
The School Mistress
Marius Goring
Lieutenant Felix Schuster
June Duprez
Anne Burnett
Athole Stewart
The Rev. Hector Matthews
Agnes Lauchlan
Mrs. Matthews
Helen Haye
Mrs. Sedley
Cyril Raymond
The Rev. John Harris
George Summers
Captain Ratter
Hay Petrie
Engineer
Grant Sutherland
Bob Bratt
Robert Rendel
Admiral
Mary Morris
Chauffeuse
