“Punters would come by and look at me, and I’d politely say ‘Hello there, are you alright?’ But then they’d do a double-take.”

It’s the actor’s latest guise, you see. The frock and the heels are all part of Rab C Nesbitt writer Ian Pattison’s latest devilish wheeze for the new series, which begins next week. Rab, we will discover, has joined the sisterhood.

It’s all a sleekit attempt to get the Government to give him more money. And it’s easy to see how a big bloke in a frock and fake breasts will offer up lots of sight-gag opportunities.

So how does the 56-year-old Fisher feel about being transformed into a female?

“I don’t think there’s anything tricky about the dressing up,” he says with a shrug. “Rab does it for a reason. He’s doing it to claim he has a gender disorder so that he can sign on the sick.

“So there’s not a lot of motivation I have to work into the performance, other than he’s a bloke who puts the gear on so he can get the dosh.

“There may, however, be a little confusion at one point. But no more, perhaps, than any bloke who has to wear women’s clothes for a fortnight.” Well, indeed.

Fisher, a former Barrhead High School pupil, points out that he’s long been prepared to check in his sense of self-awareness at the television studio desk. “Oh, yes, you have to,” he says, grinning. “Don’t forget, I’m the man who once played a ­hamburger in a series of Nesbitt.

“In my career I’ve also been a lion, in The Wizard Of Oz, and I’ve worn women’s gear quite a lot over the years.

“I’ve never been a Dame but I played Rikki Fulton’s lumber in Babes In The Wood, the King’s panto, way back in 1981, and I was the Baldy Man’s mother (in the 1995 series), which involved her having a bra full of mixed broth. The peas and barley gave the swinging bra a real honesty.”

But a male actor has to really convince as a female. Now, you’d assume that British actors would be more restrained -- particularly the Scottish actors -- thanks to the cultural-identity stamp that tells us it’s effete and frivolous to dress up, and pretend to be something you’re not.

However, Stanley Baxter, Les Dawson, Roy Barraclough and Alastair Sim have all carried the handbag with aplomb.

“I think British actors use the internal and external at the same time,” says Fisher, “whereas the American actors all seem to be happening inside -- although I don’t know why that should be.

“They’re famous for playing themselves, such as John Wayne. And even though Clint Eastwood plays a grumpy old man in Gran Torino, it’s still pretty much the same performance he gives in every other film.

“But you go with that. It’s a different style of acting.”

Other Americans have, of course, slipped into women’s clothing successfully: Dustin Hoffman in Tootsie, Jack Lemmon and Tony Curtis in Some Like It Hot, and Robin Williams in Mrs Doubtfire.

“Yes, and I did see Robert De Niro in Stardust recently,” adds Fisher. “He camped it up in a frock, playing a can-can dancing transvestite pirate. It was an entertaining movie. But the Brits drag up best.”

Will television audiences accept Rab in a dress? “They were very understanding when David Tennant once played a transvestite in the show (back in 1993). I think if the scripts are right, the audiences will go with the character -- and not in a patronising way, because there is more sympathy, more understanding these days.”

He’s right. And after all, Rab C Nesbitt isn’t about the shock value of seeing the eponymous wastrel in a wig. It works because he’s a social commentator -- a philosopher who happens, from time to time, to dress up as a hamburger, or indeed as a woman.

So what insight did Fisher get into the female psyche from donning the dress and wig? “None, really,” he says, laughing. “Because whatever way you play it, you know you’re a man standing there with falsies and tights and a pair of high heels thinking: ‘As soon as I can get this kit off, I can go hame.’

“But I have to say: I don’t understand the high-heels thing. It’s bloody torture.

“What you won’t see in the programme is that every time the director shouted ‘Cut!’, a very nice lassie from the wardrobe department brought me a very nice pair of slippers.”

Support hose apart, did Fisher enjoy returning to Rabworld? “Making the series was an absolute hoot,” he says, emphatically.

And would he sign up for another one, if the ratings merit it?

“I’d go again and again and again,” he says. “But it’s not up to me. It’s up to the powers that be -- and, of course, to Ian Pattison, if he chooses to write it.”

Just as long as there are no high heels involved.

Rab C Nesbitt begins on January 21 at 9.30pm on BBC2.