[Help Me!]

I KNEW the name Peter was in the title, but couldn't come up with anything else. Thank you so much!

[Help Me!]

Can anyone help me identify this movie? Black and white...a young boy and girl are close friends and promise to marry when they are older. They become separated when (I think) the boy's family moves. Years later as adults, they reunite, unknowingly, when the young man takes a job as the young woman's architect (?). They realize who they are...something happens...the man is imprisoned and visited daily by the woman. In the end he learns that she had been dead the entire time, therefore he was visited by her ghost.

Thank you for any information!