Ready When You are Mr McGill was a one-off comedy classic in the 70s but Sir Tom Courtney leads a star-studded remake, with the eminent actor improbably cast as a clueless film extra. Graham Keal went to met him at his London home.

ON a warm September afternoon I mount the steps of Sir Tom Courtenay's handsome, white-fronted, three-story house in a quiet street in Putney, south London, wondering if I'd done right to wear a casual shirt. I mean, him being a knight of the realm and everything.

When his welcoming wife Isabel shows me to the conservatory I see I needn't have worried. The knighted one is wearing a grey marl T-shirt with a cartoon dog on the front, dark grey shorts and battered suede trainers, so he clearly doesn't stand on ceremony.

The knighthood came three years ago and, having been reading Dear Tom, his autobiographical memoir prompted by letters his beloved mum used to send him, I wonder how comfortable he is with it. His long-departed parents would have been proud, I'm sure, but his old Uncle Dan, staunch socialist, would not.

"Oh, Uncle Dan? Phwooo... He would have reacted the most. He would have kicked up quite a stink, and been very excited," says Tom.

He's happy with plain Tom, so does he use his title? "I never, ever think about it really. Well, hardly ever. It's quite a good thing in the bank if you're not being treated very well, but a lot of people, young people, simply don't comprehend it. At the garage where I take the car they call me Sir Courtenay. It's just b****cks as far as they're concerned.

"But it was such a surprise. I never had a CBE first, which is unheard of. I don't know of any other actor who has had a knighthood without one."

Given Tom's avowedly working class roots, growing up as he did close to Hull's Fish Dock where his father was a ship's painter, had he ever considered declining the honour?

'It was really for my father that I thought I ought to accept it... The trouble with declining is what Eileen Atkins said - if you don't think you can keep your mouth shut about declining, you shouldn't decline.

"I also thought it might help with the work - America is very snobbish."

And did it help with the work?

"No."

With or without a knighthood, Tom has been showered with sufficient honours, nationally and internationally, to command respect. He won a richly deserved BAFTA (his second) for Best Actor for his last TV film, A Rather English Marriage, in 1998, and has had two Oscar nominations.

Now he has a new TV movie to promote, a remake of the late Jack Rosenthal's 1976 comedy classic Ready When You Are Mr McGill. The original was a brilliant 50-minute satire on the perils of TV drama production, showing how an exasperated, exhausted, nervy director is taken to the brink by an amiable, star-struck and incompetent extra who has one line and can't get it right.

Bill Nighy plays the director this time (after Jack Shepherd) and Tom plays the extra, Mr McGill, a minnow among media sharks who was actually played by an extra in the earlier film.

"I never saw the original but I think they've enlarged the whole thing - I don't know whether he enlarged the part I play but, I mean, I'm not an extra."

The feature-length update was Jack Rosenthal's final script and boasts a stellar cast including Amanda Holden playing not only herself but also the star of Police Siren, an episode of which Bill Nighy's director is struggling to complete on schedule. Phil Davis, Sally Phillips, Stephen Mangan and Tamzin Greig are all in there too.

Real-life director Paul Seed also directed Tom in A Rather English Marriage, so the film's pedigree could not be bettered. No wonder Tom is angry about the tribulations involved in getting it before the viewers.

Mr McGill will be fluffing his line on Sky Movies 1 today and September 29 (having debuted on September 15) but the ITV1 airing expected when the film was in production has yet to materialise.

"I don't know what happened. I wish I did, but I don't know what the answer is. There may not be one. But it's such a good script, there are such good people in it and it meant so much to Jack. He was there every day. I think he was more poorly than we knew, and maybe he thought it would be his last thing... But the whole thing was done very lovingly and well."

Jack Rosenthal died in May this year after a long battle with cancer, so he did not live to see it on screen. ITV still say they will show it when they find a slot, but that's another reason why Tom has a few expletives to delete on their apparent reluctance.

"The film has been treated like a piece of ****, frankly, and it isn't a piece of **** at all...

"Paul Seed was terrific on A Rather English Marriage and none of us had any idea that it would work out, but of course that was a terrific success, one of the biggest BBC2 has ever had. That was thrown out by ITV too - quite at the last minute...

"ITV decided that people weren't interested in old people, but of course, the people who watch television are old people."

Casting Tom as the hapless but human Mr McGill is rather ironic: not only has he never been an extra, he has never even been a rising star. He started right at the top and just stayed, sometimes enduring gaps in his film career but continuing to wow theatre audiences throughout and never taking on work that he could not put his heart into.

His first role straight after RADA was as Konstantine in a hugely successful Old Vic production of The Seagull, which he also performed in Edinburgh and which established a lifelong affinity with Chekhov.

Straight after that came his first film, the lead in iconic 1962 Britflick The Loneliness of the Long Distance Runner, winning him his first BAFTA. He became even more famous the following year with Billy Liar, gaining the film role after taking over the stage part from his RADA pal (and English Marriage co-star) Albert Finney. Dr Zhivago soon followed.

More plaudits came when Tom teamed up with Finney to play the homosexual dresser in the 1983 film of The Dresser, based on Ronald Harwood's play inspired by the touring career of Donald Wolfit.

Tom had starred in the play too, a milestone in more ways than one. He met second wife Isabel on the production. "Isabel was stage manager when we started in Manchester and she came with it when we took the play south," he says.

They have been together ever since and seem very comfortably so, even though he says he can't remember when they married: "I honestly don't know. I count being together more really than the actual marriage."

Career-wise he is now "raring to go" after what he terms "a medical year" when he took time out to fight an illness which he does not care to disclose.

Tom's next role is a Radio 4 play due in October, in which he assumes a status way beyond that of knight. "It's called A Brief Interruption. God hears this radio play and thinks it's a bit boring so He interrupts with a few words. I play Him."

* Dear Tom (Doubleday) £16.99

* Ready When You Are Mr McGill shows on Sky Movies 1 tonight and September 29, both 8pm. ITV still plans to show the film, but no transmission date is fixed.