Cast
William Collier Sr.
Mugs O'Flaherty (uncredited)
Warren Hymer
'Lug' Kaufman
Joseph Depew
Naval Reservist (uncredited)
Walter C. Kelly
Chief Mike 'Guns' Costello
Steve Pendleton
Ens. Richard 'Dick' Cabot (as Gaylord Pendleton)
Walter McGrail
Chief Joe Cobb
Ferdinand Schumann-Heink
Adolph Brucker (uncredited)
Marion Lessing
Anna Marie Von Steuben
Jack Murphy
Naval Reservist (uncredited)
Maurice Murphy
Merkel (uncredited)
Harry Strang
Gunner and drill sergeant (uncredited)
조지 오브라이언
Cmdr. Robert 'Bob' Kingsley
Hans Fuerberg
Fritz Kampf (Second Officer of U-172) (uncredited)
Harry Tenbrook
Winkler (uncredited)
Francis Ford
Eric - Captain of Trawler (uncredited)
Nat Pendleton
'Butch' Wagner (uncredited)
Mona Maris
Fraulein Lolita
Henry Victor
Baron Ernst von Steuben (U-boat commander)
John Loder
Franz Shiller
Larry Kent
Lt. 'Mac' McGregor
George Harris
Naval Reservist/Swimmer and Diver (uncredited)
Edward Peil Jr.
Naval Reservist (uncredited)