For Disney fans, he is best known for having been the original voice of King Louie in The Jungle Book. He also recorded the 1974 concept album Let's Hear It for Robin Hood, in response to the fact that he was not given a part in Robin Hood.
Prima's and Keely Smith's rendition of "That Old Black Magic" was also the subject of a DTV music video (set to footage of, among others, Magician Mickey and the "Sorcerer's Apprentice" scene from Fantasia), which aired on the Disney Channel and was included on the DTV: Golden Oldies video release. This version of the song was also made famous by Jim Henson in his earliest Muppet shows, Sam and Friends, with Sam performing as Prima and a cross-dressing Kermit the Frog as Smith.
Prima was supposed to provide the voice of Louis in The Rescuers, but he suffered a massive heart attack in 1973, and he died five years later; therefore the project of his inspiration, Louis the Bear, was unfortunately scrapped and eventually became that of a deleted character from the movie.