The Ipcress File (1965)

Sly and dry intelligence agent Harry Palmer is tasked with investigating British Intelligence security, and is soon enmeshed in a world of double-dealing, kidnap and murder when he finds a traitor operating at the heart of the secret service.
Sidney J. Furie, Pat Moon, Fred Slark
Michael Caine, Nigel Green, Guy Doleman, Sue Lloyd, Gordon Jackson, Aubrey Richards, Frank Gatliff, Thomas Baptiste, Oliver MacGreevy, Freda Bamford, Pauline Winter, Anthony Blackshaw, Barry Raymond, Peter Ashmore, Stanley Meadows, David Glover, Mike Murray, Anthony Baird, Tony Caunter, Charles Rea, Ric Hutton, Douglas Blackwell, Richard Burrell, Glynn Edwards, Zsolt Vadaszffy, Josef Behrmann, Max Faulkner, Paul S. Chapman
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