It's the nonsensical tune that became the catchiest Muppets song of all. And Mahna Mahna, which hit the top end of the charts in 1977, is about to worm its way back into the public consciousness all over again. Not only is there now an official website that invites fans of Kermit the frog, Miss Piggy and friends to record their own version, but it takes centre stage in the new Muppets movie, currently playing in UAE cinemas. It's a pleasing development, not least because songs have always been a key part of Muppet mythology. After all, the very first line of the theme tune to The Muppet Show announces that "it's time to play the music". Mahna Mahna was broadcast on that show's 1976 premiere, with two hot-pink "Snowths" continually interrupted by a wild purple Muppet with orange hair (the titular Mahna Mahna) bawling his own name to increasingly amusing effect. But there is a coda to the scene that sums up the irreverent, devil-may-care nature of the puppeteer Jim Henson's enduring creations. "The question is, what is a mahna mahna?" says Statler, one half of the critical Muppet double act Statler & Waldorf - the two grumpy old men always seen in the balcony. "The question is, who cares," corrects Waldorf. Lots of people, as it turned out. The Muppet Show, for the uninitiated, grew out of Sesame Street, Henson's educational children's television programme that first introduced us to the antics of the puppet frog Kermit, Big Bird and many more. Henson was wary of being typecast, so, in a move that seems positively revolutionary these days, he pitched the idea of a primetime variety show where the audience was also taken behind the scenes to witness the ensuing chaos. Oh, and this programme would be populated and presented by his Muppets, with a special human guest star each week. The Muppet Show may have seemed ridiculous, but it worked. Millions tuned in every week and, as it began to rack up Emmys and Baftas, the queue of celebrities wanting to appear got longer. And these big-name guests didn't just turn up and play their music. In 1977, Elton John, goggle-eyed and resplendent in an array of multicoloured feathers, somehow pulled off the trick of looking more ridiculously unreal than any of the Muppet characters dancing all around him. True, with its childlike "Nah, Na-Na-Na-Na, Nah" chorus, Crocodile Rock sounded as if it had been written for this specific performance in mind. But even Elton John couldn't have imagined he would one day be accompanied by both the Muppet house band Dr Teeth and the Electric Mayhem, and howling laughter. The fun didn't end there: the end of the song saw the bespectacled Rocket Man fall into a swamp and then greeted by a host of happy crocodiles. Later, he performed Don't Go Breaking My Heart in a pink jumpsuit - describing Miss Piggy as "a lady I've always wanted to work with" - somehow all with an entirely straight face. Which is more than Johnny Cash managed when Miss Piggy gatecrashed his performance of Jackson in 1980, dressed in a stetson. Still, he kept his composure - humouring the prima-donna's terrible singing and giving her a nice hug at the end. Elsewhere in the series' four-year run, drummer Animal ruined Rita Moreno's smouldering version of Fever (she had the last laugh, smashing him on the head with a cymbal); Gonzo called Twiggy Leafy, Barky and Branchy; and Shirley Bassey appeared not to mind that all eyes were on the group of pigs robbing the bank vault, rather than her performance of Goldfinger. And if that was all good-natured fun, nothing quite matched the frankly bizarre sight of Alice Cooper detailing the nocturnal terrors of a child called Steven during his performance of Welcome to My Nightmare, while Muppet backing band The Vile Bunch merrily strummed along in the background. Just for good measure, later in the show Cooper revealed that he was an agent of the devil, and offered the Muppets fabulous riches and fame in exchange for their souls. The Alice Cooper episode was surely the perfect distillation of Henson's initial vision. This wasn't a kids' show with pop stars performing bland versions of their recent hits: instead, adults could nod knowingly at the format - which essentially poked fun at the variety shows filling up 1970s television schedules - and the ironic humour. Children could enjoy the silly costumes, outlandish jokes and visual gags. And the guest stars knew they were a part of something that would genuinely be talked about - as long as they entered into the spirit of the show. Can you imagine, in almost 40 years time, the same being said about, say, Justin Bieber's performances on Late Show with David Letterman? Of course not. And even when the Muppets themselves were the musical stars, the results have generally been hugely memorable. In November 2009, their version of Queen's classic Bohemian Rhapsody was released and became a viral hit within days. Notably, when Queen permitted the Muppets to use the actual backing track, the guitarist Brian May said on their website: "We don't often do this - it's only because of our respect for these people as artists that we'd do this. I'm sure Freddie would feel the same way ... some projects are just worthy of a proper collaboration." It felt like May had actually forgotten he was talking about a bunch of cloth puppets. In the new film, there are plenty of new songs given the inimitable Muppets treatment - including Cee Lo Green's Forget You (by Camilla and the Chickens) and Nirvana's Smells Like Teen Spirit (by The Muppets Barbershop Quartet). Happily, the story - the Muppets regroup to try to buy back the theatre used in the television show, but face crushing indifference from the networks - is as self-aware as usual. Of course, it features Mahna Mahna. Not bad, really, for a tune that started life as a throwaway ditty by composer Piero Umiliani for, er, an Italian "adult" movie set in a Swedish sauna. And as frankly bizarre stories go, isn't that so very Muppets?