As an artist, Frank Zappa had famously always done whatever the hell he wants. As a comedian, John Belush had taken the same risks. So when Zappa appeared as a musical guest on Saturday Night Live in December 1976 to perform “Purple Lagoon” anything could have happened. And did. Belushi went ahead and jumped into the band, started a call-and-response routine, and then attempted to play the sax.

Zappa came back in 1978 as host and musical performer again, and this time, performed “St. Alfonzo’s Pancake Breakfast” and “Rollo.” Where’s Belushi? Just wait until the 1-minute mark…