B&W 1960(?) movie about a man who is a uni lecturer with a delusional disorder. Set in theme of the cold war, He believes he is a russian (?) spy. In his mind he has a setup in his garden shed and delivers information in an envelope to a house that the viewer eventually sees to be derelict. Last scene is him returning to his uni after treatment knowing he has hallucinations related to the cold war and characters he encountered in his delusional state.

Your description sounds an awful lot like "A Beautiful Mind." Not 1960's though, and not black and white: http://en.wikipedia.org/wiki/A_Beautiful_Mind_(film)

Your description sounds an awful lot like "A Beautiful Mind." Not 1960's though, and not black and white: http://en.wikipedia.org/wiki/A_Beautiful_Mind_(film)

Thanks - it isn't A Beautiful Mind. The film is set in B&W and dress, cars etc are definitely 1960's or earlier. Perhaps A Beautiful Mind is a re-make of the original.