BUtterfield 8 (1960)

This is the kind of lurid Hollywood melodrama I love. It follows the torrid love affair between a Manhattan call girl (Elizabeth Taylor, in one of her finest performances), and a tormented businessman (Laurence Harvey). 

There's an interesting subplot with Eddie Fisher as Taylor's long-time closest friend, and the film spends a good deal of time examining their relationship and the tension that it causes with Fisher's fiancee.

I'd been meaning to see this one for a while. I'd heard in an interview that George Kuchar cited it as a big influence on his own films, which made me even more curious to see it.