It sounds like Hitchcock's Spellbound.
Rick Provine wrote:
> A faculty member asked me about this film. Ring a bell for anyone? I need
> a title...
> > The idea of the story was this: a man had been witness to or
> >somehow involved in a crime - murder probably. He could not remember
> >the incident due to trauma induced amnesia or some other cause. The
> >mystery was eventually solved through the language of dreams. The man
> >had a recurring dream about a wheel spinning in a void (this image was
> >in black and white - the rest of the movie may have been too, but AGAIN,
> >I don't remember!). Finally, a psychiatrist determined that the
> >recurring image of the spinning wheel represented a "revolver." This
> >was the key and the mystery was solved. There was a great deal of
> >suspense which my synopsis can't convey. I recall being riveted.
> Rick E. Provine
> Director for Media||Robertson Media Center
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