Beside featuring big and colorful characters, children's shows rely on a catchy songs to draw in viewers. So naturally, there's a lot of work that goes into selecting a tune. While some write their own original music, others often borrow from other sources.
In 1976, when Jim Henson and his Muppets landed their own television shows after years of appearing on shows like Sesame Street, the show runners opted to use a song that was relatively popular in the late 60s for their opening sketch - "Mahna Mahna."
According to the popular version of the song's origin story, it was first heard during one of the sketches on the first season of Sesame Street in 1969. The Muppets performed the tune on The Ed Sullivan Show, as well as on other variety shows before reprising it for the debut episode of The Muppet Show.
However, what many don't know is that the Muppets' song wasn't an original, and when it was first released it was associated with a very different type of audience.
Italian composer Piero Umiliani wrote the first version of the song for a special "mondo film" project and released it in 1968.
The song, which was spelled as "Mah Nà Mah Nà,” gained popularity in Europe when it was featured on the soundtrack of the documentary Sweden: Heaven and Hell.
Guessing by the title, you'd assume the documentary is probably about the pros and cons of living in Sweden, but that's not correct. The documentary, which was geared towards Italian audiences, actually explored sexuality in Sweden.
That's right, the catchy Muppets tune had its origins in a soft-core porn film.
The song made an entry into the charts shortly after, but only managed to reach #55 on the U.S. charts. Despite its minor popularity, the nonesense songs was catchy enough for Henson to name a Muppet Mahna Mahna and the rest became history.
Even today, the "Mahna Mahna" phenomena is still going strong. The song was featured in the Muppets' 2011 movie, and most recently, Mahna Mahna and the Snowths performed the song at the 2017 Hollywood Bowl.