What happens when pop reunions turn toxic?

Producers, promoters and publishers turned down Melanie Blake's story The Thunder Girls for two decades because it's about four women in their 50s, the writer says. Now the tale of a former girl group is a book and sold-out play.

Pop reunions are big business, but one thing fans are even more fascinated to see than their idols back on stage is how they really get on behind the scenes (or not). The response to the hilariously revealing Bros documentary proved that.

Melanie Blake saw the truth about pop stars' personal relationships while working on Top of the Pops in the 1990s, as a journalist and then as an agent. She used to manage Bros's Luke Goss, as well as Steps' Claire Richards and Spandau Ballet's Martin Kemp.

While she was a freelance journalist, a magazine assigned her to write about life on a 1980s reunion tour. "I went on the tour bus. It was absolutely hell," she says.

"Everybody hated each other. People wouldn't talk to each other, and then they'd be like, 'Hello Wembley!' and they'd sing their songs, and then they'd all come back and immediately get in different parts of the bus and wouldn't speak to each other."

The Thunder Girls is her deliciously bitchy story of an '80s girl group who get back together to discuss a reunion 30 years after a toxic break-up.

"Every band from Fleetwood Mac to Steps and the Rolling Stones have got missing members and have all had these meetings," she says. All five Spice Girls met up last year, she points out - but only four ended up going on the reunion trail.

"Every band that reforms has to have a reunion dinner to see if old wounds can be healed enough so that the blood stops seeping whilst they're on the stage. That's what nobody ever sees."

The Thunder Girls are meant to have been prototype Spice Girls, and certainly have girl power. But their wounds run deep. Resentment and jealousy about romantic betrayals, financial skulduggery and career-ending bad behaviour have built up over decades.

Blake, from Stockport, wrote the first version in 1999. She eventually published the Thunder Girls novel in July and used the book advance to finance a stage version starring Coronation Street's Beverley Callard, Nolan sister Coleen, Emmerdale's Sandra Marvin and ex-EastEnders star Carol Harrison.

The characters have to decide whether a big pay cheque can overcome the fact that they hate each other's guts. There are some fabulously catty lines. "Did you have a lift on both of your faces?" asks the hard-up Roxie, played by Callard, of Harrison's Chrissie, who has overshadowed her former bandmates as a TV talent show judge and tabloid favourite.

Nolan plays Anita, who dropped off the radar after a disastrous Eurovision appearance. As one of the Nolans, one of the biggest groups of the late '70s and early '80s, she also brings some insight.

"Oh my God, I've known bands over the years that genuinely, apart from when they're on stage, can't stand each other," she says. "They all have separate dressing rooms and separate cars. But when they're on stage, it works."

Despite the fact that Blake managed the Nolans' lucrative 2009 tour, they insist that was one reunion that did not inspire The Thunder Girls. "We were sisters, so there was no toxic fallout," says Nolan.

The Thunder Girls stage show, directed by Joyce Branagh (sister of Sir Ken), is on at The Lowry arts centre in Salford for just five nights and broke the record for the fastest ticket sales for a new play in the venue's Quays theatre.

It has gone down particularly well with women of the same age as the characters, who can relate to the themes of ageing and long-term friendships.

Blake is already talking about taking it to London's West End, and the initial response is vindication after two decades of being told that a story about four middle-aged women would never work.

"First it was picked up as a book. And then publishers said 'Well, we'll do it, but we think it should be based on younger women.' And I said no."

Then the rights were optioned by a TV company, she says. "They came back and said 'We like it, but we think they should be 35.' I said, 'No, they have to be in their 50s because they have to be women. They have to have lived, loved and lost.'

"And then last year, when we started looking at the stage show and we started looking at investors and promoters, they were all like 'What, four women? Over 50? Singing? And they actually still think they're it, do they?'"

Callard, best known for playing Liz McDonald in Coronation Street, says ageism and sexism are still rife in the entertainment world.

"More often than not you look at a film script, or you look at plays or films or television things that have been made, and you would get 10 male actors in it and maybe two women if you're lucky," she says.

"More often than not, you would see a husband who's maybe 50 with a 30-year-old wife. It happens all the time.

"Our business is so sexist and so anti-women. When Melanie told me about this play, and when I read it, I just said 'I've got to do this'. Because it's about real women."

Speaking during a break in rehearsals, Blake says a male-dominated force in the entertainment industry ("Let's call it 'the man'") has tried to dictate what people want to see.

"It shouldn't be the case that there's only one woman in every show, or that there's only one older woman. I've just watched four women over 50 smash it.

"It's electric because they've lived lives. Too many people like to write women off with expiration dates. Women don't have expiration dates. Life only makes them more interesting."

The Thunder Girls is at The Lowry in Salford until 28 September. Melanie Blake's novel is published by Pan Macmillan.

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