This B&W movie "36 Hours" is now being repeated on digital TV quite regularly, and I never tire of watching it. The WW II storyline, written by Roald Dahl & Carl Hittleman, is an odd one. It has to be one of the most implausible, yet somehow believable tales ever to be thought up.
A US "hospital" run by Nazi Intelligence has been set up in Germany to enable secrets to be winkled out from it's "patients" (i.e. prisoners). The gimmick is that the inmates are led to believe that the war has been over for a number of years in favour of the Allies.
The new arrival a certain Maj. Jefferson Pike (James Garner) is an Overlorder (i.e. someone who is "au fait" with the plans of the forthcoming Normandy landings). After being kidnapped in Lisbon he is brought unconscious to the hospital and given necessary ageing treatment. On regaining consciousness he is told that he is suffering from amnesia, and has been a hospital patient for years, but he must now start remembering.
A disguised Wehrmacht psychiatrist Maj. Walter Gerber (an American born German, but a good guy at heart) (Rod Taylor) is given the task of unlocking the valuable knowledge. If he fails, he and his hospital are for the chop. (And the Allies will succeed in their invasion etc. etc.) Anna Hedler, his nurse, and supposedly Pike's wife, is an ex-concentration camp internee (Eve Marie Saint) who will do anything not to be sent back. End of stage one, but will the secrets come out in stage two?...watch the movie to find out.
"36 Hours", ably directed by George Seaton, is an intriguing movie that holds the attention right to the last. It's an intelligent script, complemented by intelligent acting, with suspenseful music holding it all together. Not exactly a classic, but I certainly think it will last the test of time (and on reflection...I suppose it already has done). Personally I love it.