Ring of Spies

The film is based on the actual events of the Portland Spy Ring trial in the U.K. A disgruntled Navy Clerk is transferred to a secret research establishment and is subsequently black-mailed/paid by Czech intelligence to procure secrets for them. He seduces the secretary who controls the most secret documents, and they enjoy the fruits of their treachery until the British authorities begin to close in on them.

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  Robert Tronson
• 
  Derek Cracknell

• 
  Bernard Lee
  Henry Houghton
• 
  William Sylvester
  Gordon Lonsdale
• 
  Margaret Tyzack
  Elizabeth Gee
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  David Kossoff
  Peter Kroger
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  Nancy Nevinson
  Helen Kroger
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  Thorley Walters
  Cmdr. Winters
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  Gillian Lewis
  Marjorie Shaw
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  Newton Blick
  P.O. Meadows
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  Philip Latham
  Captain Ray
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  Cyril Chamberlain
  Anderson
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  Justine Lord
  Christina
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  Patrick Barr
  Captain Warner
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  Derek Francis
  Chief Supt. Croft
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  Hector Ross
  Supt. Woods
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  Paul Eddington
  Johnnie (uncredited)
• 
  Richard Marner
  Colonel Monat (uncredited)
• 
  Geoffrey Palmer
  Police Officer (uncredited)
• 
  Bryan Pringle
  Surveillance Man (uncredited)
• 
  Andre Mikhelson
  Russian Embassy Official (uncredited)
• 
  Garry Marsh
  First Member at Lords (uncredited)