|Pingu's Dream (Original 1990 Audio)|
The 21st episode of Pingu, titled Pingu's Dream, in itself could have become a lost episode. It was banned after a few unknown airings for the walrus being too frightening for children. It wasn't shown in the United States for a while, and was pulled from television in the United Kingdom when it aired in 2003. Later on, it was only released in a couple of DVD/VHS releases containing the first season, an example is the American DVD Antarctic Antics, and it did air once on PBS Kids Sprout in 2006, saving it from becoming fully lost, though there were some edits made so that the episode was not as frightening to young viewers.
The audio of the walrus terrorizing Pingu was changed for the home video releases. In the original May 12, 1990 airing, when the walrus would pop out and reveal himself to Pingu in the nightmare, it would roar and squeal, instead of laughing in the edited version for the episode. It's been said French airings used this version, but this is yet to be confirmed.
It is likely that this audio will remain lost, as it only occured in the original 1990 airing.