Disney's Greatest Villains was a one-hour television special that first aired on May 15, 1977 on The Wonderful World of Disney. It was a somewhat updated version of 1956's Our Unsung Villains, and was also used to feature Madame Medusa, the villain in the then-upcoming Disney animated film The Rescuers.
The program was hosted by Hans Conried reprising his role as the The Slave of the Wicked Queen's Magic Mirror from Snow White and the Seven Dwarfs and other Disney specials. The Mirror explained the importance of villains, with most of his dialogue taken from Our Unsung Villains.
Clips from various Disney films were featured, with the Magic Mirror providing biased, yet humorous, commentary. Most of the Villains received a good-sized clip from their respective films, although some were featured in a very brief 30-second segments. One sidenote is that the music featured in Madame Medusa's segment would not be used in The Rescuers.
Disney's Greatest Villains would be shown again in reruns, the last time being on the Vault Disney block of programming on the Disney Channel. In 1983, portions of Disney's Greatest Villains were incorporated into the 90-minute special A Disney Halloween. In the UK, it was released on video around the same time.