Seas Beneath

In the waning days of WWI, a U.S. "Mystery Ship," sets sail for the coast of Spain towing a submarine. Their mission is to find and sink a U-boat that has been especially effective in attacking Allied shipping. Posing as a harmless schooner, the mystery ship is in fact fitted with a formidable gun capable of sinking a U-boat. Stopping in the Canary Islands to refuel, the crew interacts with locals involved with Germans, and with Germans themselves, including the sister of the U-Boat commander, who is lurking offshore waiting for the coming battle.

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  John Ford

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  George O'Brien
  Cmdr. Robert 'Bob' Kingsley
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  Marion Lessing
  Anna Marie Von Steuben
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  Mona Maris
  Fraulein Lolita
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  Walter C. Kelly
  Chief Mike 'Guns' Costello
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  Warren Hymer
  'Lug' Kaufman
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  Steve Pendleton
  Ens. Richard 'Dick' Cabot (as Gaylord Pendleton)
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  Walter McGrail
  Chief Joe Cobb
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  Larry Kent
  Lt. 'Mac' McGregor
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  Henry Victor
  Baron Ernst von Steuben (U-boat commander)
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  John Loder
  Franz Shiller
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  Philip Ahlm
  German Chief Petty Officer (uncredited)
• 
  Al Bennett
  Naval Reservist (uncredited)
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  Earl Wayland Bowman
  Naval Reservist/Swimmer and Diver (uncredited)
• 
  Bill Brande
  Naval Reservist (uncredited)
• 
  William Collier Sr.
  Mugs O'Flaherty (uncredited)
• 
  Leonard Davison
  Naval Reservist (uncredited)
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  Joseph Depew
  Naval Reservist (uncredited)
• 
  Francis Ford
  Eric - Captain of Trawler (uncredited)
• 
  Robert Ford
  Naval Reservist (uncredited)
• 
  Hans Fuerberg
  Fritz Kampf (Second Officer of U-172) (uncredited)