The Very Loud Threat To Our Children

This is Frank in Paris in 1980 performing the title track of his rock opera Joe's Garage, which is all about making music illegal. In keeping with the conceit that it's a public service announcement by the people who have made music illegal, Joe's girlfriend runs off with the roadies of a rock band and Joe falls in with Lucille, "who gives him an unpronounceable disease," leading to the second song in this video (which begins about 2:30 if you want to stop it).

Yes, that's right: Zappa went there. Later on in the opera, Joe keeps slipping into worse shenanigans. It's a sort of a "fatal glass of beer" story, with mad axe riffs instead of alcohol.