36 Hours (1965)
36 Hours takes the typical concept of a war movie and tosses it out the window, instead giving us a cynical, suspenseful, psycho-thriller that will make you smirk, think, and it will surprise you.
James Garner plays US Army Major Jeff Pike, who's dispatched to Portugal on a mission just before D-Day. He's privy to the details of operation Overlord, and the Germans know it. Through their nasty network of Nazi spies they manage to kidnap him, and then the real fun begins.
Read the rest of this great review of 36 Hours at 36 Hours (1965) starring James Garner, Eva Marie Saint, Rod Taylor