Most musicians see the pop world stretching out before them and they consider it as a long line with art at one end and cash at the other. They set a limit on how far in each direction they are prepared or able to go, and they get to work. In 2009, Lady Gaga decided that this world was not flat. In fact, from her vantage point orbiting pop, she could see the line between art and commerce bending round so that the two extremes of art and commerce met at the top. She stuck a flag in that spot at the top and called it Bad Romance.
Expectations were hardly low. In 2008, Poker Face and Just Dance had been hits around the world, and she'd already begun wearing gas masks and Kermit capes in interviews or simply to walk down the street, but Lady Gaga's fourth top 10 single marked the coronation of the download era's first pop superstar. It was also the song whose irresistible energy and success elevated Gaga to a level where Madonna comparisons became commonplace.
Written by the then 23-year-old Gaga on her tour bus in Norway and produced by long-term collaborator, Morocco-born, Sweden-raised RedOne, Bad Romance is a song about being in love with your best friend, as well as being perpetually drawn to the wrong people in general. If its message lacks the self-conscious aspirations of some of Gaga's current work such as Born This Way, the song's importance – as with most truly significant pop songs – is less about educating the world, more about brutal effectiveness as a piece of music. Also in the mix were fearsome beats, a clever second verse that references the work of Alfred Hitchcock (Rear Window, Vertigo and Psycho are all mentioned), a decadent, preposterous middle eight in which Gaga starts singing in French, some almost subliminal growls of "I want your bad romance", and a moment when the song collapses under its own weight, the silence pierced by an earsplitting howl of "WHHARRGHYOUBARROWMANCE!".
An earlier, demo version had leaked in the autumn of 2009. It was pretty good – it sounded a bit like Poker Face – but it lacked a certain something. That something turned out to be the kitchen sink, and by the time of the song's official debut at Alexander McQueen's Paris Fashion Week show in October, Bad Romance was firing on all cylinders. Even two years and several hundred listens later, the densely packed but crisp-sounding production continues to throw up new sounds and surprises.
The video director Francis Lawrence, who directed Hollywood blockbuster I Am Legend, constructed a four-minute parade of 12-inch footwear, razor blade sunglasses, Thriller-style dance moves, white latex suits and massive gyroscopes. It was also the first glimpse of Gaga's signature move as she contorted her hand into the shape of a claw, an easily copied gesture which subsequently became the focal point of the slightly overegged interaction between Gaga and her fanbase, whom she calls her Little Monsters.
Set in what seems to be a Russian bath house, the Bad Romance video told the story of women sold into sex slavery. Gaga is force-fed vodka by models, dances for prospective clients, who bid for her, then finally led to a bedroom which she duly sets on fire. By the end of the song, the anonymous man who has apparently "won" an evening with Lady Gaga is a smouldering skeleton while the singer herself is content to enjoy a post-arson cigarette by his side as pathetic sparks splutter from the tips of her bra.
When Lady Gaga arrived in the UK to promote the single with a performance on the X Factor she moved on from the kitchen sink, instead appearing with 10 dancers, all of them taking the stage while sat inside a 20ft bathtub. Dressed as a bat, she broke out of the song two thirds of the way through in order to perform an abstract version of the middle eight on the piano, but sat on a white toilet bowl rather than the usual stool. Both silly and euphoric, like the closing scene of the video, it added playful, comic touches to this extraordinary tune.
Eventually, Bad Romance managed 10m global sales and 360m YouTube views. Then there was the record-breaking US airplay, the Grammy win, the seven MTV VMAs and the No 1 in countless countries including the UK, where it hit the top spot twice.
The way was paved for Gaga's current success and cultural ubiquity: the album Born This Way sold more than 1m copies during its first week of release in the US, while in this country it replaced 21 by Adele – a pop star cast from a rather less complicated mould – at No 1. Some critics felt that the material on the new record – 17 tracks plus remixes on the special edition – was either not enough like Bad Romance or too much like Bad Romance. No matter: the four-minute blast that cemented her position as a megastar will stand for ever as the defining pop song of the digital age.