A tugboat captain serves under his rival as a U-boat chaser in World War I.
John Thorson
'Rocky' Blake
Susan Thorson
District Commander
U-Boat Captain
'Cap' Finch
Milo
Ives
German U-Boat Officer
Admiral Ross
U-Boat Petty Officer
Ensign Dyer
Admiral Girard
Recruiting Officer (uncredited)
Fisherman (uncredited)
Listener (uncredited)
Radio Operator (uncredited)
