All the fun of the flare

Ah, the Seventies. We all remember the Seventies, don't we? All loon pants, space-hoppers, glam-rock and tank tops? The author Jonathan Coe revisited the decade for his 2001 novel The Rotters' Club, which has just been made into a three-part BBC television drama by the people behind Shameless. Coe discovered a different 1970s from the one peddled by the retro-kitsch industry. "The ironic approach to that decade has been robbed for all its worth," he says. "I wanted to do something a bit more authentic and get back more to the spirit of the decade as I saw it."

Ah, the Seventies. We all remember the Seventies, don't we? All loon pants, space-hoppers, glam-rock and tank tops? The author Jonathan Coe revisited the decade for his 2001 novel The Rotters' Club, which has just been made into a three-part BBC television drama by the people behind Shameless. Coe discovered a different 1970s from the one peddled by the retro-kitsch industry. "The ironic approach to that decade has been robbed for all its worth," he says. "I wanted to do something a bit more authentic and get back more to the spirit of the decade as I saw it."

These were "brown times", according to Coe, through his teenage narrator, Benjamin Trotter. The Rotters' Club tells of his Benjamin and his siblings, Lois and the horribly precocious Paul (the Trotters are known as the Rotters at their grammar school, hence the title) as they come of age in 1970s Birmingham. What Coe calls the spirit of the age - the political polarisation and strife - is reflected in their father Colin's position as a middle-manager at the British Leyland plant at Longbridge. The Birmingham pub bombings, Grunwick, the birth of punk rock and the roots of Thatcherism are also in the mix, but the core of the book is set in a school based squarely on Coe's Alma Mater - King Edward's in Edgbaston. Indeed his inspiration for The Rotters Club was the Lindsay Anderson film, If..., in which gun-toting sixth-formers take over a public school.

"I liked the way Anderson's film uses a school - with all its power struggles, cliques and rivalries - as a microcosm of British society as a whole," he says. An admiration for this auteur of the radical Free Cinema sits perhaps a little oddly with his choice of screenwriters to adapt the book: Dick Clement and Ian La Frenais, of Porridge and Likely Lads fame.

"It was my idea to ask Dick and Ian," says Coe. "They were my idols in the 1970s. At a time when my fellow novelists-in-waiting were all probably reading Proust and Henry James, I was learning their sitcom scripts off by heart. Indeed, the rhythms of the dialogue in my novel were taken directly from The Likely Lads, so it's perfect - and rather unbelievable to me - that they have ended up adapting it."

"That's very flattering," says Dick Clement.He and La Frenais originally adapted the book for Channel 4, but when the new dramaturgs there dropped the project, BBC2 picked it up, expanding the original two hour-long episodes into three.

"We had to change the time-frame," says Clement. "The young characters in the book go from 14 to 18 and you can't do that unless you're doing Harry Potter and one a year." So while Coe's book stretches from 1974 to 1978, the TV adaptation ends in 1977, at a street party to celebrate the Queen's jubilee - scenes that were never in the novel.

The other hurdle in adapting Coe's book was the meandering, many-headed nature of the plot. Bill Anderton (the shop-steward father of Benjamin's friend, Doug) is having an affair with his secretary at Longbridge, while Barbara Chase (the mother of another school-friend, Philip) is contemplating an affair with one of the boys' teachers. And these are just two of several barely overlapping storylines that Clement and La Frenais had to develop within a three-hour framework.

"We've always written well for large bunches of people," says Clement. "We're fairly good at handling a lot of characters. There were similarities here with Auf Wiedersehen, Pet, really, where you had seven people in a room and we had to share out dialogue."

The casting proved less problematic than the writing - even in the absence of starry lead roles. "It's an ensemble piece, but quite a lot of the actors liked it because they liked the characters," says the producer, Chrissy Skinns, who signed up Hugo Speer, Julian Rhind-Tutt from Green Wing, Mark Williams from The Fast Show and Sarah Lancashire among the adult parts. Lancashire says: "I knew as soon as I read the script I wanted to be part of it." She plays Chase, the neglected wife and mother led into temptation by the philandering art master Nigel Plumb (a gleeful performance from Rhind-Tutt).

Barbara's cuckolded husband, Sam, is played by Mark Williams, using a hideous pair of sideburns he wore in The Fast Show. "I am exactly the age that the book was written about," he says. "I was going through all that in Birmingham in 1974-75. Philip's bedroom on the set was decorated for a poster for a concert I actually attended at Birmingham Town Hall. The lead band was supported by unknowns called Queen..."

The pivotal role of Benjamin Trotter went to a second-year drama student called Geoff Breton. But if there is a star of the Rotters' Club adaptation, it is the 1970s themselves - their weird and wonderful fashions, and, retrospectively, their rather innocent sense of cool and sophistication. "I find the fashions of the time - and attitudes of the time - less funny than touching, really - it seems a naive period now," says Jonathan Coe.

The Rotters' Club was mostly filmed on the Isle of Man, serendipiditously, it seems, for the costume researchers. "It's so back-in-time over there that a lot of the clothes were actually found in Oxfam shops on the island," says Skinns, who was also helped by the Seventies look re-emerging on the high street. "One or two tops that might look period had actually been bought that day at Top Shop," she says.

Ironically it was the element of The Rotters Club that should have been most fun - the music - that proved the trickiest. In the book, Benjamin and his friends move from progressive rock ("nobody called it prog-rock at the time," says Dick Clement) to punk rock - forming their own band - The Maws of Doom - in the process. All the wonderfully long and portentous progressive rock pieces (performed in the TV series by Natalie Imbruglia's backing band!), as well as the subsequent punk numbers, were created by the series composer Martin Swain.

For the episode where Doug is sent to review a punk band by the NME, the production team stumbled across a current punk band called Neil's Children. "They're doing punk again," says Skinns. "We didn't have to change the way they looked or change the music; it was absolutely perfect for the start of punk."

The trouble came with sourcing original Seventies songs for background music. With the necessity of selling The Rotters' Club abroad (and particularly to the US) international rights to a lot of songs became prohibitively expensive. "Where Steely Dan are mentioned and you want to have them playing in the background, it's too expensive on a BBC show to get copyright clearance for the US," says Skinns. "That said, I just found out today that we can have The Stranglers."

Jonathan Coe followed up The Rotters' Club last year with a sequel, The Closed Circle, which meets up again with the characters now under New Labour - they are middle-aged and disillusioned. Coe and Dick Clement are both keen to do a TV sequel. Clement decided, however, to suggest that the younger cast members didn't read The Closed Circle.

"I thought it would inhibit them," he says. "If you knew what's going to become of you when you're 18, it would colour your attitudes." Coe agrees whole-heartedly. "I was struck by the freshness and enthusiasm of the young cast, and to hand round my new book, which showed their characters as cynical and disillusioned, seems a rather unconstructive thing to do. Cruel even."

'The Rotters' Club' starts at 9pm on Wednesday on BBC2