Jackie magazine closed over 20 years ago but it now has its own Seventies clothes range

Jackie magazine closed in 1993. But with a musical based on the million-selling weekly, and now a clothing line for ASOS, the brand refuses to fade away

Back in fashion: Jackie has become a powerful brand

A few years ago, the journalist and broadcaster Nina Myskow was at the BBC to promote a coffee-table book celebrating Jackie, the bestselling girls' magazine of the 1970s. Myskow, who had edited the title between 1974 and 1978, had provided its introduction, and required little excuse now to wallow in nostalgia. So there she was, striding down one of the BBC's many corridors with a copy of the book under her arm when, she says: "I passed a smart, intelligent-looking and no doubt very powerful female executive. As soon as she saw the book, she started shrieking and clutching at me, as if she had become 12 years old again. I had to wrestle it back from her."

Odd behaviour, one might think. But no, Jackie seems often to have this effect on, as Myskow suggests, women of a certain age. "Oh, for women in their late 40s, early 50s, it's a time machine. It can take them right back to childhood."

Though the magazine folded in 1993, its publishers never fully let it go. And for good reason: in 2015, Jackie has become a powerful brand, so much so that its publisher, DC Thomson – a famously straightlaced, family-run operation – now employs someone with the very 21st-century title of "head of brands" to oversee its multi-media reach.

The revival began in 2007, when EMI Records wanted to release a series of Seventies-themed compilation albums featuring scream-appeal acts such as David Cassidy, Donny Osmond and Marc Bolan. They needed a hook and thought immediately of Jackie. DC Thomson was understandably enthusiastic, and were positively rapturous after the albums shifted more than a million copies. Books followed, with Carlton publishing a Jackie annual which sold 100,000 copies, comfortably more than most Booker winners. Thomson's head of brands, Tim Collins, was now a kid in a candy store. A snowball effect ensued. On Monday, the result of a collaboration between the magazine and online fashion retailer ASOS goes live, featuring a range of Seventies-influenced clothes, all with, Collins insists, "not only the Jackie label, but a contemporary edge."

And coming soon is Jackie the Musical, which will tour the country for the next 12 months. Against a backdrop of the era's most memorable and cheesiest hits, the narrative revolves around a fiftysomething divorcée who returns to her stash of archived Jackie magazines for much the same reason she first consulted them decades previously: advice on how best to navigate the opposite sex.

The show had its initial run in Dundee in 2013, and was a big success. "The audiences were amazing," says Andy Dear, one of its producers. "The shouts, the screams, the cheers! We were, to be honest, completely blown away by the reaction."

Myskow is less surprised, but then she knows more than most about the brand's lingering resonance. "It really does mean an awful lot to a great many women," she says. "It was a kind of big sister to them at a very important time in their lives, and this was of course way before the internet, before YouTube. They were convinced they were the only ones in the world going through that transition of being a child still, but becoming a woman. It offered its readers a kind of security; it was invaluable." Jackie is perhaps the most unlikely publishing phenomenon. Launched in Scotland in 1963 by the staunchly Presbyterian Thomsons, it recognised that girls were no longer in the grip of a postwar austerity but had become a definable group in themselves: namely, teenagers, a pocket money-funded demographic that found its voice through music and fashion, and required a bible on both. Jackie was twee and conservative and very deliberately chaste, but it resonated with its readership in a way that Roy of the Rovers never quite managed with boys.

Seventies style: A fashion spread from Jackie

It was an instant success. "But our sweet spot came in the 1970s," says Tim Collins. "We were selling 600,000 copies a week, and then, within a year, that figure had risen to a million-plus. The volume was staggering, really."

In addition to its popstar profiles and photo-love stories was the problem page, Cathy and Claire, the agony aunts on hand to deal with the myriad problems puberty throws up. Many letters were deemed unsuitable for publication but during Myskow's reign they endeavoured to answer each problem personally; no mean feat when they were receiving upwards of 500 letters a week. "I just felt that if young girls took the time to write a letter, express themselves, then find a stamp and an envelope, they deserved a reply," Myskow says.

In this way, the magazine saw successive generations through into adulthood, all competition firmly in its shadow. But time galloped on and Jackie didn't. By the 1990s, its continued straightlaced approach to teenage life was starting to seem anachronistic, not least compared to the likes of More! magazine, whose demographic might have been early 20s but whose readership was far younger. More!'s content was racier and provocative; the more infamous its Position of the Fortnight feature became, the more copies it sold. Jackie, of course, had never strayed into the murky world of the Kama Sutra.

Jackie, oh: fashion spreads in the Seventies girls' magazine have inspired online retailer Asos to bring out a line of clothing

"When I was at the magazine, kids weren't pressured in the way they are now," says Myskow. "What we were trying to do was prepare them as much as possible for life by instilling in them a feeling of self-worth and self-esteem, a spirit of independence so that they could have confidence in themselves."

She recounts a story about Emma Thompson, the writer and actress, who wrote in when she was 12 years old, asking them to print a photograph of her father Eric, the man behind Magic Roundabout. The magazine regularly printed photographs of pretty boy popstars, and Thompson was convinced her father was better looking than most.

"We printed it, of course," says Myskow, whose later career took her to Fleet Street, where she frequently bumped into Thompson, by now a famous star, and with whom, thanks to the magazine, she felt in some way inextricably linked. "The last time I interviewed her, I took along a copy of The Best of Jackie. She screamed with delight. Extraordinary, but very typical. It was that kind of magazine."

ASOS Reclaimed x Jackie collection is available on asos.com from 4 May