Have a second look to see if you can guess who the actor is. You saw him on TV in the 60s and 70s. That's his real-life sister Vilma dancing with him, which will help you not at all. An odd note: if they are living on the roof - and not the tallest roof around - where do they change? What are their nightclothes? 30s movies were notorious for introducing such sexual elements without a shoulder being shown or even a passing reference to a body part. The audience is titillated without quite knowing why.
He was also Doc Holliday in "Breakfast at Tiffany's," a supposedly romantic movie that is carried by the fact that Audrey Hepburn is so adorable and people like to think they can get away with being "unconventional" like that. It is otherwise just strange and even creepy.