Sometimes a Fantasy (is hard to figure out!)

This past week I was discussing with a listener a Billy Joel song that had just played on KONA Radio. I recalled I saw the video once in 1980 and it subsequently disappeared from TV after that. I think it was the repeated “crotch shots” towards the end of the video. Anyways I rediscovred it on Youtube just now and the video just confuses the heck out of me. I forgot there was another guy in the room with Billy Joel as he was on the phone. In fact the other guy was BIlly Joel in disguise. I just couldn’t figure out the dynamic. Anyone got a clue as to what the story is about? Here’s the video:

or a direct link :