When Marcus Brigstocke takes to the stage tonight to host the reborn Saturday Live, he does so with several weights on his corduroy-clad shoulders. There’s the pressure of reviving a name that became all-but synonymous with alternative comedy in the 1980s, making stars of its regulars, Ben Elton, Harry Enfield and Fry and Laurie. There are the technical requirements of telling jokes while people shout in his ear-piece and burly men set up Bon Jovi’s drum kit just out of camera shot. And then there’s the fresh discipline of bringing his tart political comedy, thus far confined mostly to Radio 4 and BBC Four, to an ITV1 audience. “Yes, the lawyers all want to [[ know every word I’m going to say,” Brigstocke says. He lowers his voice conspiratorially: “But between you and me, it’s going to be live.”

Several of the reborn Saturday Live’s acts are familiar faces – Jimmy Carr, Mitchell and Webb, Lee Mack, Ben Elton. Some of them are closer to the sort of bubbling-under cult status that we associate with the original – the magician Pete Firman, the sketch trio We Are Klang, the drunken children’s entertainer Jeremy Lion. But however experienced tonight’s turns, few of them – the returning Elton aside – know much about performing absolutely live to millions of people. Even America’s long-running Saturday Night Live – the show’s inspiration – is prerecorded then edited at speed.

Geoff Posner, the director and producer of both the original and the revived show, admits that live Saturday night shows are commonplace. “But that’s usually talent shows, not comedy. Live comedy is a real rarity.” And while there is a lot of comedy on the margins these days, late at night or tucked away on a digital channel, this show is mainstream. It’s edgy comedy, centre stage on primetime. “That’s exactly what the challenge is,” Posner says. “We are taking ITV into areas that it hasn’t been for a while. We’re effectively bringing back – and I hesitate to say this – a variety show.”

Few of the ardent viewers of the original three series, which ran from 1986 to 1989, would have cared to classify it as anything so 1970s as a variety show. This, after all, was earth-shaking satire, sure to bring down the reign of “Thatch” via the street poetry of Craig Charles, the bright comments and shiny suits of Ben Elton, and the television debuts of comics such as Jo Brand, Paul Merton and Julian Clary, whose acidic irreverence provided welcome relief from the regressive hegemony (we used to talk like that back then) of comedians such as Russ Abbot and the Two Ronnies. Harry Enfield gave us the aspirational Stavros and the vulgar Loadsamoney, a no-messing rebuttal of the Greed is Good decade. Variety show? No way. This was revolution, and sketches and stand-up were our spears and guillotines.

Actually, hindsight, brought into focus by the recently released best-of DVD from the first series, suggests that it was a revolutionary variety show. Thatch, as we know now, was not all that vulnerable to a routine by Lister from Red Dwarf, however incisive. And the crowds were often resistant to Elton’s more biting material – “bit of politics, bit of politics” was a catchphrase born of Elton’s ironic acknowledgement of this. But, harnessing some of the talent with whom the co-producer and co-director Paul Jackson had worked on The Young Ones (Elton, Rik Mayall and Ade Edmondson) and scooping up the best acts from a comedy circuit that was still in its infancy, they gave legitimacy to their young performers. And, with only four channels for viewers to choose between, they could afford to take risks.

“When we started, there were five comedy clubs in London,” Posner says. “So television was giving a little push to a form of live entertainment that hadn’t actually existed before. It gave a leg-up to individual performers, but also to the industry itself.” In short, it carried the banner for alternative comedy. “But the alternativeness was not so much what they were talking about, but where they were doing it,” says Posner. “There was a great feeling when we were doing the show. There was a feeling that they were all part of something.”

Tonight’s comeback has plenty of big names, but then the programme always used a Trojan horse approach.

The first series, which used the guest-host format borrowed from Saturday Night Live, was fronted by stalwarts such as Lenny Henry, Tracey Ullman, Pamela Stephenson and Peter Cook. Ben Elton became the regular host only in the second series, after Frankie Howerd dropped out. Alongside him and the other regulars would tend to be a well-known British comic, a less-known British comic and an American act. “The new bill,” Paul Jackson says, “is very much comparable to the bills we had back then, in quality and in flavour.” And if Elton sometimes struggled with his political moments, Jackson suggests, a lot of stand-ups struggled in that big noisy room, with some of the crowd milling around on the studio floor, some of them whirling around on fairground rides (there was always vomit to be cleaned up every week) and the rest of the studio audience sitting some distance away. “It’s a big noisy studio,” says Jackson, “and you need to be a very good comic, very focused, to win in that environment. Lenny Henry did the pilot and he’s someone who can win over any room. But not everyone can do that.”

The original series ended because the principals were starting to do shows of their own: “We sort of felt our work was done,” Posner says. But its influence was huge – from tonight’s performers alone, Mack and Brigstocke have admitted that it’s what turned them on to alternative comedy, while, if you were casting around for a 21st-century Fry and Laurie, your first stop would be Mitchell and Webb. But comedy is everywhere now. Can this new show possibly have the impact of the old?

“No,” Posner says, “and nobody knows that more than me. Everything is different. The best that we can do is say that we are doing something in the spirit.”

Brigstocke, who arrived at rehearsals yesterday after three days of hosting BBC Four’s live satire show The Late Show, sees this very much as the successor to the 1980s show. They have been considering a routine, he says, summing up the two decades since the last show. Does that mean the previous attempt to revive Saturday Live, done with Lee Hurst in 1996 without Posner or Jackson’s involvement, is something they don’t like to talk about? “No, we don’t talk about that,” says Brigstocke. “So much so that I hadn’t remembered it had happened till you mentioned it just now.”

Variety shows are invariably variable, but even if tonight’s attempt doesn’t fulfil its huge promise, producers will keep searching for the holy grail of a contemporary Saturday Live. Its original master, Channel 4, will be launching its own Saturday night show, hosted by Russell Brand, in the new year. BBC Three is mounting something similar, provisionally titled The Wall. But if this Saturday Live can indeed win over the sort of mainstream audience that panel shows enjoy, it will surely be mission accomplished. In fact, if it’s a ratings success, could it even return for a whole series? “We’d love to do more if this goes well,” Jackson says. “Our phone,” Posner says, “is always manned.”

Saturday Live Again, Sat, ITV1, 9.40pm; Saturday Live – The Best of Series One is out now on DVD

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