Twenty-five years ago, Frankie Goes to Hollywood were the biggest British pop group since the Beatles and the most controversial since the Sex Pistols. They had just spent nine weeks at No 1 with their second single, Two Tribes, the 12in version of which, subtitled Annihilation, was propelled by an immortal bass line and featured almost 10 minutes of lavishly orchestrated (by the producer Trevor Horn and the arranger Anne Dudley), thunderous disco rock, interspersed with air-raid sirens and voices instructing us — at the height of the cold war — what to do in the event of nuclear attack.

Its predecessor, a blast of synthe­sized boogie called Relax, which extended to a positively tumescent 16 minutes on the 12in Sex Mix, had been banned by the BBC for its allusions to orgasms, although that didn’t prevent it reaching No 1 and becoming the seventh best-selling single ever in the UK.

By the time the third single (and third No 1), the sumptuous ballad The Power of Love, came out in November 1984, people were so accustomed to scandal from the Liverpudlian five-piece that they took one look at the Nativity scenes filmed by Godley & Creme for the accompanying video and imagined sacrilege where there was none. Frankie were pin-ups and pariahs.

“I would always defer to Boy George,” says Holly Johnson, considering the question of who the biggest pop star in Britain was back then, walking through Fulham to the house he has shared with his boyfriend, Wolfgang Kuhle, since Frankie’s heyday. The front man does, however, concede that his was a more subversive presence than his quaintly flamboyant rival’s. Indeed, Johnson and the band’s dancer and backing vocalist, Paul Rutherford, were talked up by their record company, ZTT, as “ferocious homosexuals”. “George was more cuddly and accessible,” Johnson decides. “I was the dangerous option.”

One of Frankie’s brilliant coups was to have Johnson and Rutherford out front, while the three token straight men — collectively known as the Lads — did all the handy work, with Brian “Nasher” Nash on guitar, Mark O’Toole on bass and Peter “Ped” Gill on drums. They were the Matlock, Cook and Jones of the piece; Holly and Paul were a double dose of Johnny Rotten, only with a fierce gay agenda.

“What we had that the Sex Pistols didn’t was the inflaming of people’s sexual morality,” says Johnson, pouring tea in his front room, surrounded by art books and his own paintings on the wall. “The Pistols had a political aspect, but they didn’t challenge people’s sexual values.” He compares Frankie to the Rolling Stones in the 1960s and David Bowie’s Spiders from Mars in the 1970s, acts who offended polite society with the threat of promiscuous abandon, although in this case, as Johnson states: “We were saying, ‘Lock up your daughters and sons.’”

He is less keen on the notion of Frankie — bolstered as they were by Horn’s sonic bombast and the arch sleeve notes and scams of the NME journalist-turned-marketing strategist Paul Morley — as a sort of high-tech, avant-garde boyband. “Take That,” he declares, “are incredibly popular, but completely unchallenging in respect of society and its mores.” Frankie came from a different milieu, he says; an early-1980s scene where groups such as Soft Cell and the Human League daringly “stretched the boundaries of normality”. Nobody pushed the sonic boundaries in the 1980s like Horn, but, despite his signature being writ large all over Frankie’s releases — that “Wagnerian grandeur on synthesizers”, as he puts it — he is keen to stress that, without the input of the five members, they wouldn’t have made history.

“You can talk about production all you want, but the idea was there,” says Horn, who points out that Gill and O’Toole proposed that Frankie should combine the rock theatrics of Kiss and the pulsating proto-electro of Donna Summer. The “beautiful bass line” under­pinning Two Tribes was also O’Toole’s, and as for those song lyrics, which caused so much furore in 1984, they were Johnson’s, as was the band’s image-consciousness. “That all came from Holly, a painter with a certain vision. People like me, we enable people. It’s my job to turn somebody’s idea into a reality. But you have to have a band that people are interested in, and for that year people were interested in Frankie — they were funny, different, something new, and they looked great.”

Horn knew that ZTT, the label he founded in 1983 with his wife, Jill Sinclair, and Morley, was on to a winner when Top of the Pops nervously agreed to allow Frankie to perform Relax in January 1984, with the condition that “there should be no messing about, naked women or bad behaviour”. “That,” Horn decides, “made me think, ‘This could be really good!’” It was this air of menace, as much as the technological arsenal Horn brought to bear on the sound, that “kicked Relax into the stratosphere”.

If anything, Two Tribes — probably the only example of rock subversion where the record is not scratchy and raw, but over-produced; what Horn describes as “aggressive in a lavish way” — was an even greater phenomenon. It sold millions and sent shockwaves around the country, as Frankie-mania took hold in summer 1984. “It was like riding a rocket,” says the producer, who witnessed queues round the block for Frankie product at a record shop in Bournemouth. “In my whole career, I’ve never seen anything like it.”

Much of this success, although this was a heretical contention in the Frankie camp, was due to the ingenious marketing of Morley. By means provocative and playful — references to obscure philosophers and manifestos, adverts that resolutely refused to say simply “out now”, those T-shirts, emblazoned with his slogans (Frankie Say War! Hide Yourself, Frankie Say Arm the Unemployed), that became fashion must-haves — he subverted the idea of pop manufacture, like a dissident Simon Cowell.

“The group would have been quite happy to be more conventionally packaged,” says Morley, who insists he was merely trying to make them seem “bigger, stronger, bolder, in the way that Trevor took their songs and made them bigger, stronger, bolder”.

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