36 Hours (1964)

During World War II, a US Army intelligence officer is captured by the Germans and subjected to an elaborate deception to make him reveal crucial information. He is given a new identity and placed in a hospital, where he wakes up with no memory of the past six years. As he tries to piece together his past, he uncovers a web of psychological manipulation and mind games. With the help of a psychiatrist and a fellow officer, he must escape from his captors and prevent a devastating attack on D-Day.