I'm not sure what the title is , but I have a one hour documentry on vcd that I got in a trade with Luca ( Hangman on this site a few years ago ) from I believe US TV , it features footage of the Hammersmith concert for the people of kampuchea and features the actor Peter Wyngard ( spelling ? ) in full costume , as Klytus from Flash ! , this doc dates from early 1980 - is this the one you're thinking of ?