The Black Windmill (1974)

A British agent’s son is kidnapped and held for a ransom of diamonds. The agent finds out that he can’t even count on the people he thought were on his side to help him, so he decides to track down the kidnappers himself.
Don Siegel, Kip Gowans, Angela Allen
Michael Caine, Donald Pleasence, Delphine Seyrig, Clive Revill, John Vernon, Joss Ackland, Janet Suzman, Catherine Schell, Joseph O’Conor, Denis Quilley, Derek Newark, Edward Hardwicke, Maureen Pryor, Joyce Carey, Preston Lockwood, Molly Urquhart, David Daker, Hermione Baddeley, Patrick Barr, Yves Afonso, Del Baker, Murray Brown, Les Conrad, George Lane Cooper, Brenda Cowling, Robert Dorning, Roy Everson, Nancy Gabrielle, Jill Goldston, Charlie Gray, Peter Halliday
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