Beneath the 12-Mile Reef

Mike and Tony Petrakis are a Greek father and son team who dive for sponges off the coast of Florida. After they are robbed by crooks, Arnold and the Rhys brothers, Mike decides to take his men to the dangerous 12-mile reef to dive for more sponges. Mike suffers a fatal accident when he falls from the reef leaving Tony to carry on the business. But now he has a companion, Gwyneth Rhys.

• 
  Robert D. Webb

• 
  Robert Wagner
  Tony Petrakis
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  Terry Moore
  Gwyneth Rhys
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  Gilbert Roland
  Mike Petrakis
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  J. Carrol Naish
  Socrates Houlis
• 
  Richard Boone
  Thomas Rhys
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  Angela Clarke
  Mama Petrakis
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  Peter Graves
  Arnold Dix
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  Jay Novello
  Sinan
• 
  Jacques Aubuchon
  Demetrios Sofotes
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  Gloria Gordon
  Penny Petrakis
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  Harry Carey, Jr.
  Griff Rhys
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  Rock Hudson
  Narrator (uncredited)
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  Jack English
  Doctor (uncredited)
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  William Johnstone
  Crewman of 'Snapper' (uncredited)