can't remember name of this old, b&w movie

I don't remember much about the movie as I watched it many years ago, but I do remember the ending: the main character a woman (who I think was an actress?) drops on purpose the keys to her apartment in front of a crazy/stalker/homeless man that always watched her throughout the movie and was always deemed dangerous.

The movie ends with this man grabbing the keys and opening the door to her building.

Does anybody remember the name of the movie?

I searched google and imdb with no avail.

DELETED

There's absolutely no reason to retroactively remove your request if it's "not needed" any more. And if it's not needed because you found the answer, the considerate thing to do is to post it here, in case someone else ends up looking for the same movie.

Hello Tin. Well if your still interested in knowing the answer to your movie question I'm quite sure I have it for you. It's "The Roman Spring Of Mrs Stone" from 1961. I have it in my DVD collection and I'm fairly sure it's in colour. Your description of the parts you remembered in the movie is excellent.