In the opening monologue, Michael Palin stuffs several cats into his pants. One of the cats defecated in his pants. Palin did not have time to cleanup before the next sketch in which Dan Aykroyd can be seen showing his disgust at the smell.
According to his memoirs, preparing for the previous episode (Christopher Lee/Meat Loaf (1978) ), Christopher Lee rehearsed for the Sherlock Holmes sketch eventually performed by Michael Palin.