Leslie Phillips is playing Falstaff with the RSC, but to those admirers who accost him on the Tube, he will always be Dr Gaston Grimsdyke. By John Walsh. Photograph by Trevor Ray Hart
"The worst thing," Leslie Phillips confides, "the thing I really don't like, is when people catch me on the Tube and say, `Go on, say it. Say ding dong'." His whole face puckers with exasperation. "And the whole Tube turns around. I get terribly embarrassed. I almost blush. You wouldn't think I could blush, would you?"

No you wouldn't. And if you likewise can't imagine why sentient human beings could ask actors such silly things on public transport, let me remind you of the hold Mr Phillips exerts on the collective unconscious of the British. It goes back to a moment in Carry on Nurse (1959) when, coming round from unconsciousness, a groggy, bed-ridden Phillips gazes upon the lovely face of Shirley Eaton and the following dialogue ensues:

Phillips: I say. What's your name, nurse?

Eaton: Why, Nurse Bell, sir.

Phillips: Ding dong. Carry on...

It's not exactly Stoppard, but it has stuck in the public memory for nearly 40 years. And while nobody can quite remember the title of any film in which they heard Phillips say "Hell-ay-o" on meeting a comely young woman, they instantly trot it out today on hearing his name. Phillips is an icon of idiotic maleness, an embodiment of suave lechery as hopelessly outdated as the cravat and the open-topped MG. In a handful of British movies in the late Fifties and early Sixties, he guffawed and leered and preened and smarmed and hell-ay-oed at countless women, most of them either unimpressed or bewildered by such front. The smooth would-be seducer he portrayed was too obvious to be true. Just as Charles Hawtree and Kenneth Williams in the Carry On films weren't homosexuals as much as sissies, so Phillips, in Doctor in Love or Not Now Darling, wasn't so much a sexual predator as a chronically unsuccessful roue. It was the vanity of his approach that women laughed at.

"I did seem to get an awful lot of catch-phrases," he says now. "One that lots of surprisingly erudite people ask me to say is a line from that film when I was looking in the bathroom mirror and putting on some after-shave and I said, `Oh you gorgeous beast'." It must be said that Phillips's chat-up routine found many admirers. "On a chat-show once, I heard that Dr Hilary Jones, the telly doctor, had agreed to come on because I was appearing. He said it was because he wanted to be like Gaston Grimsdyke [the chortling lothario of the Doctor films] that he became a doctor. Well all I can say is, God help the National Health Service."

Celluloid seducers come in many shapes and sizes, from George Sanders in Rebecca to Charles Boyer in Love Affair, but you can count the comic seducers on two fingers: Phillips and a friend of his, with whom he has often been confused. "You should never get big-headed about being what's laughingly called a star, because someone will always come up to you and say, `Hello Mr Thomas', and you realise it doesn't really mean very much. I'm always being called `Leslie Thomas' or `Terry Phillips'." Thirteen years older than Phillips, Terry-Thomas was his spiritual uncle, playing a similiarly caddish (though gap-toothed and more sinister) corrupter of innocence in the same peculiar cultural hinterland, between Fifties stuffiness and Sixties wackiness.

Curiously, Phillips's memories are of his filmic rival's disintegration. "I made a film with him in the Seventies in Menorca, called Spanish Fly, and I realised then there was something wrong with him. He had one of those motor diseases, you know. I'd see him come in in the morning looking dreadful, and get into make-up, and come on set looking fantastic - so smooth, smoother than me, really, except for the gap between his teeth - and he'd struggle for the words, because his memory was suspect. But he wasn't really a theatre actor, you see, he hadn't come from the theatre as I had, so I was kind about it. And then I realised there was something wrong with him". Later, when talking about death, Phillips remarks, "A lot of actors, like Terry, wouldn't see people towards the end. They didn't want to be seen, especially by people who had any connection to what they did and might be going to take over their roles."

Lots of this speech is characteristic of Phillips. Without being exactly bitchy about his peers, he manages subtly to hint that he himself is the better actor, the truer thespian, the healthier body, and that his is by far the more interesting life. He is a man for whom the concept of false modesty does not exist. He is sneakily but decidedly competitive. And he is unquestionably a better survivor than most. Now 73, he is clearly turning into Trevor Howard (the Ryan's Daughter look), though he hasn't changed all that much from the Gaston Grimsdyke days. Around his neck he wears a double gold chain, to complement the efflorescence of white curls that sprout from his chest. His co-respondent's moustache is snow- white, but his sensible tweed jacket is offset by blue jeans, and his eyes are bright with mischief. As he moves from dressing- to green room, he greets young female members of the company with avuncular, though bogus, familiarity ("I resort to `Darling' when I don't know their names") and they giggle and tweet in reply as if he were about to do something, you know, really incorrigible.

He is, understandably, becoming fixated by mortality. Amazingly, you learn that he and Terry-Thomas both had houses on the Spanish island of Ibiza. "Thirty years ago," he says, "it attracted a lot of very artistic people, if I may put myself under that umbrella", who also included Denholm Elliott and Jon Pertwee. He met the former at the end of the War and had "a very strong relationship" with him (though not strong enough to be able to explain why he should have died of Aids). He and Pertwee acted together in The Navy Lark, that floating repository of radio catch-phrases - "Left hand down a bit"; "Over a bit sideways" - that convulsed radio listeners in the early Sixties. It is piquant to think of the Balearic swingers' paradise, the cradle of acid-house music, overrun with English smoothies from the Light Programme.

"I wish they were all there now," says Phillips, "but, in fact, I'm almost the only one. I go there still, but I almost lead a solo life when I go now." He sniffs regretfully. "When I started in this business, I was always the youngest in the company. Now I seem always to be the oldest. All my friends from years back are gone. It's not that I'm preoccupied with death, but it comes into an actor's life more than most people's. People can always compare you with yourself from God knows how many years ago, by switching on the TV." He is not, it seems, a fan of his younger self. He is, he'd like you to know, a serious actor. He takes life seriously. His own has not always been sexy fun. Now happily married to Angela Scoular, 20 years his junior, he has survived two dark nights of the soul, the acrimonious divorce from his first wife, Penny Bartley, and the violent death of his mother, who was mugged at 93.

Phillips gave up comedy work in the mid-Seventies, in search of more challenging roles. And, apart from a few periods of puzzling silence from the nation's casting directors, he has had a truiumphant renaissance. On television, he has played a lot of judges and high-commissioner establishment types. On stage, he has been working through the whiskery end of the classical repertoire. Last year, he was asked to join the Royal Shakespeare Company, and can now be seen on London's Barbican stage impersonating Falstaff in The Merry Wives of Windsor.

Wasn't he a little too cool and suave to play the fat roisterer convincingly? "Yes, I've always been a thin actor. And of the two Falstaffs, the heavy and the light, I'd probably be better at playing the heavy one [from Henry IV] than this... nut. This Falstaff is more difficult because it isn't very deep, so you have to find all the depth yourself." The Falstaffian girth requires a lot of padding to achieve its full bell-like magnificence. This brings its own problems, upon which Phillips discourses with fluency. "The biggest problem with making him very fat is that I become very dehydrated. It's one of the most energetic roles in Shakespeare, and I become so heated, it affects my voice. Drinking liquids is no good, because it doesn't get to the larynx. The only thing that works is steam. I've arranged to have a steam machine on stage. It goes into my mouth and up my nose and straight to the larynx." He pats his throat. "They talk about steam radio and steam trains. This is steam acting."

And that, by and large, is all Mr Phillips wants to say about his role. Perhaps he feels that the spectacle of Falstaff pressing his suit with two ladies simultaneously (Susannah York and Joanna McCallum), being bundled into a basket and chucked in the Thames, re-surfacing in a bath with a rubber duck, and ending up antlered, gulled and mock-executed in a woodland populated by eldritch children, isn't quite the image of sober classicism he was hoping to project (though he's very good in the part, his voice mellowed into the richest, sleepiest instrument that ever tried to part a Windsor matron from her underwear).

Working at the RSC has been an eye-opener for him, he says, because of the atmosphere of "corporate directing", he says. Which means? "There are a lot of things in this company I've never met before, and I'm glad I have because it's got me over a lot of hang-ups." Such as? "Well - I don't really like acting in front of people, and being criticised and watched until I'm ready. I don't mind making a fool of myself, but I don't like having all the actors sitting around watching you, and almost waiting for you to fail. I've always had a problem with that. But it's very much the RSC way. Everyone contributes, and they say what they think, quite openly. I think that's done me a lot of good, though I couldn't do it at first. I was so self-conscious." Did he offer comments on other people's acting? "No, no," he says firmly. "I always hide in the corner. I was brought up to be quiet and sit at the back."

That is, when he wasn't being taught to project as a child actor. He was born in Tottenham in 1924. The family (he had an older brother and sister) moved to Chingford in Essex when Leslie was nine. His father worked for a company that made gas cookers ("When you walked down Angel Road, where the factories were, it always smelt of gas"), and his death left the family in penury. Phillips's mother took in sewing, and his siblings got jobs, but "I realised we were near the breadline". Responding to an advertisement for child actors, she took the 10-year-old Leslie to meet Italia Conti, the diva of drama teachers, who was impressed by the way he twirled his cloak while reading from Julius Caesar, and signed him up. He has acted ever since.

"People were terribly kind to us kids," he says, a refrain he returns to now and again. "All the big theatre stars, they were very sweet to us. I had no trouble. None of that trouble." He wrinkles his nose in distaste. "You know... sexual problems." You mean, abuse? "Nothing like that. Nothing," he says with surprising vehemence. "I didn't know much about what went on at all. I was quite surprised when I grew up." He sounds a little puzzled still.

His conversation is full of the most silken kind of name-drops, from his time being "taken up" in his teens by both of Laurence Olivier's wives, Vivien Leigh and Joan Plowright, to his more recent offers of work from Jonathan Miller, Peter Hall, Derek Jacobi and Anthony Hopkins, who directed him in his behind-the-camera film debut, August. "Tony saw me in The Cherry Orchard, and gave me the part. I became good friends with him. Great guy. Wonderful man. He was pleased when he heard I was going to the RSC. He said, `I'd like to direct you in Lear.' But whether that will ever come to pass... I think," Phillips concludes with understandable fondness, "he's the best actor in the world."

Leslie Phillips as the King. Gaston Grimsdyke on the blasted heath. It's a weird thought, but no weirder than anything else in Phillips's eclectic career. He is now contemplating writing his memoirs, for which he has been offered a substantial advance by Macmillan the publishers.

The title? "Lots of people think I should just call it Hell-ay-o," says Phillips with a groan. "Though John Barber, the critic, once told me, `When you write your memoirs, you must call them From Bed to Worse'." Well, yeah. But what's wrong with From Leer to Lear?