Jupitus is at home on stage and in Edinburgh

"I'm very much wearing the number twelve shirt," Jupitus says on a break from rehearsals. "Ross signed up to it first, but then he couldn't do the opening few weeks, so they asked me instead. I've never been in rehearsals for the start of something before. I've always stepped into it once it's been up and running, so it's a slightly new experience for me."

Despite this, Jupitus has long been versed in the mores of Brooks' original 1968 film based around a pair of Broadway hacks who realise they can make more money from a flop than a hit.

"I've been trying to work out when it was that I first saw it," Jupitus says, "I clearly remember seeing it as a kid, and that there were a lot of in Jewish references that a ten year old boy in the home counties wouldn't get, but he's such a great writer, Mel Brooks, and I think I may have seen Blazing Saddles first.

"It was the days before video, so it would be on the telly when you were fifteen or sixteen, and you'd be ringing up your mates to tell each other it was on, and it was like nothing we'd ever seen. As a teenager in the UK, comedy was about Monty Python, Morecambe and Wise or The Good Life, all these straight-up sit-coms and weird British humour, whereas Mel Brooks was so exotic. I think I'd seen Woody Allen's film, Bananas, by then, which also had this quick-talking New York Jewish humour, but I'd really never seen anything like Mel Brooks, so to be in The Producers today is absurd."

The Producers isn't Jupitus' first stint at musical theatre, having just appeared on the West End in Urinetown: The Musical, while he was previously in Hairspray and Monty Python's Spamalot. Despite such high-profile shows, as well as his elder statesman status as the longest surviving panellist on TV pop quiz Never Mind The Buzzcocks over nineteen years, Jupitus isn't shy of getting back to his Fringe roots.

As well as reviving Porky the Poet for the Edinburgh Free Fringe, Jupitus has taken part in the Traverse Theatre's early morning Theatre Uncut seasons of hot off the press plays performed script-in-hand . He has also become one of the alumni of White Rabbit Red Rabbit, Iranian writer Nassim Soleimanpour's theatrical experiment in which one performer picks up a script in a sealed envelope having had no rehearsal, with what follows remaining a secret between actor and the audience. With the likes of John Hurt and Stephen Rea having done the show since it was first seen in 2011, no-one has given the game away yet, and Jupitus isn't going to spoil things.

"The Traverse asked me to do it about three years ago," he says. "I said to them, look, don't be shy of asking me to do things because you think I'll be too busy, so it's great. When I knew I was doing White Rabbit Red Rabbit I happened to bump into Marcus Brigstocke, and he said he'd done it, but he wouldn't tell me anything about it. It's such a clever thing to do."

Such a willingness to take a chance on things has been the hallmark of Jupitus' career since his early days supporting bands as Porky the Poet. Even that came about by accident during a time when he was working as a civil servant with what was then the DHSS in the mid 1980s.

"It was about the time the ranting poets came out," Jupitus says. "You'd had the Liverpool poets, and you'd had John Cooper-Clarke, and later you'd get the likes of Craig Charles and Lemn Sissay coming off the back of that, but at that time you had Attila the Stockbroker, Seething Wells, Joolz, Benjamin Zephaniah, Little Brother and others coming in off the back of punk. Some of them were amazing, but there were others that weren't, and I remember thinking I could do better than that, and I didn't even do it."

It was Attila the Stockbroker who persuaded Jupitus to take the leap onstage after finding tow poems in a folder full of illustrations which Jupitus had been working on. Jupitus ended up working a fertile live poetry circuit as well as supporting the likes of Billy Bragg.

"At that time in the eighties," Jupitus recalls, "you could earn as much as you would on benefits doing gigs, and doing gigs was much more fun."

Jupitus packed in the DHSS and toured with Bragg, for whom he made a couple of videos, also working for Bragg's record label, Go Discs. As with most things in Jupitus' career, a move into comedy came about by accident, when fanzine writer and NME journalist James Brown, who would go on to found Loaded magazine, gave him some friendly advice.

"James said that the things I said inbetween the poems were funnier than the poems themselves," Jupitus recalls, "and that was the first time I realised I could be a comedian. I was talking with Alan Davies and Jo Brand about how we all fell into it, and not one of us could remember a moment where we decided to be a comedian."

For The Producers, Jupitus is particularly looking forward to the tour's Edinburgh dates, where he and so many of his peers cut their performing teeth.

"It feels like home," he says of the city, "and to come back outside the Fringe is such a buzz. It feels like a village where everyone knows someone who knows someone, and I love to go to all the art galleries. Four of my favourite bars are there, and if I've got a pocket full of change in one of them I can work their jukebox for hours."

Such are the perks of Jupitus' happily wayward career.

"It's either this or an office job," he says, "and as I found out in the mid-eighties, a nine to five isn't something I'm really cut out for."

The Producers is Festival Theatre, Edinburgh, March 23-28; Theatre Royal, Glasgow (with Ross Noble), June 15-20.

www.theproducersmusical.co.uk