Don't pay the Ferryman - Chris de Burg
Doctor Who #4 Tom Baker is in the video iirc.
It's the teeth.
That was one of my top 5 favorite 80's songs.
Edit: I found the "original" video on a couple sites through Google video. Low quality, I can't find it on youtube at all and on many other sites it is "no longer available"
Anyway, here's a screencap of the low quality version I did find. The wiki article on the subject says both Chris & Tom deny it's him.