Lear complex

Ever since Yes Minister, Nigel Hawthorne has been gearing up to give us his Lear. Consider the evidence. His great performances find him portraying dignified figures of authority whose moral and emotional steadfastness is undermined by ill health and / or domestic strife. CS Lewis, George III, Clarence in Richard III, his grim Malvolio in Trevor Nunn's Twelfth Night, and now Edgar Pascoe in Paula Milne's new drama for Channel 4, The Fragile Heart: a full house of crack-ups. So when can we expect to see him tackle Lear, that Everest among Shakespearian peaks? "Oh, you mustn't put me up to things like that," he says admonishingly. "There are too many precedents. I'd much rather do something original. I don't really want to follow in other people's footsteps. Never have."

Hawthorne's contention is that The Fragile Heart is Lear - not a preparation but a substitution, not Everest, perhaps, but a Himalaya of comparable steepness. This interview being his sole outing on the drum-banging promotional round, there's an element of "he would say that, wouldn't he?". And yet, though Milne is not Shakespeare, there's every sign - in The Politician's Wife, Hollow Reed and now The Fragile Heart - that her work is deepening and darkening as the notes of compassion and cynicism in her voice strive for a rich, complex harmony. Note Pascoe's Christian name, and his duplicitous daughter: perhaps this Edgar really is a son of Lear.

Edgar Pascoe is a leading cardiac surgeon of impeccable reputation: he is ineffably polite to the patients whose dicky tickers have enriched him, but somehow distant and mechanistic, as all surgeons must be. His belief in the relentless advance of medical technology admits of no doubt. Nor does his scorn for alternative treatments. He does triple bypasses to a soothing soundtrack of classical music and professional small talk. A star performer on the conference circuit, he quietly promotes the career of his daughter who, unlike her twin brother, has succeeded in going about her father's business. He is medical aristocracy, at the head of a dynasty.

Even as these brush strokes are daubed on to the canvas, shadows are also massing. A patient dies under Edgar's scalpel, and the widow threatens legal reprisal. Fissures appear in his marriage: his wife, a country GP always dutifully under his spell, develops an interest in holistic cures. Though he doesn't know it yet, his daughter is making incisions with her surgeon's knife into the backs of colleagues. And then there are his bad dreams of the dark figure who sits in the room as he sleeps; the furtive readings of his own blood pressure; the grim prediction told by his own stethoscope.

Another role, another blind man painfully seeing the light. It's all grist to Hawthorne's mill, but when he was first offered the role, he declined. "It had none of the depth and none of the passion that it eventually had. When I was given the script a second time, I jumped at it because she'd written it beautifully and the ideas which came from it were very much in sympathy with the sort of things I'd been moving towards. They're quite dangerous subjects for me - like mortality - which I don't really choose to face up to."

Hawthorne, a vegetarian and confessed vitamin-abuser, is an instinctive disciple of the alternative treatments that the drama seeks to show in a positive light. Like the Pascoes, his was a medical family. His father was a GP who transplanted the family to Cape Town when Nigel was an infant. "We lived very near a public swimming pool. People were always bashing their heads and breaking their arms, and so, as kids, we were all called in to hold the patient while he did the thing he had to do." Hawthorne was not expected to go into medicine but his father, a caring doctor but "rather Victorian and impatient" as a paterfamilias, had specific ambitions for his offspring that did not encompass thespianism.

"He was extremely angry. He used to talk about me joining the diplomatic corps ... I was always very envious of his traditional education. Mine was, I suppose, colonial, not the same at all. I knew I'd found my vocation and just was astonishingly liberated by this choice and it answered all sorts of questions for me about expression of identity that I hadn't really come to terms with."

While inviting Hawthorne to confront the inevitable outcome of advancing years - he is a fit 67 - The Fragile Heart also held the threat of more tangible perils. Pascoe's work as a cheerleader for telemedicine - operations conducted via satellite link-up - takes him to communist China. Milne's portrait of the black market in prisoners' organs is just a little inflammatory, so Taiwan deputised for China during filming, but a Taiwan whose waters were being aggressively patrolled this summer by the Chinese navy. "We were there three months ago. It was just after the warships were circling round. Brian Eastman [the producer] was talking about filming in Taiwan and I said, `Whereabouts in Taiwan?' He said, `Oh, I think we're going to quite a safe area'."

These days, when Hawthorne goes abroad to film, it's usually to Hollywood, and it was partly the expectation of more work from there that made him dither over The Fragile Heart. (He's more or less through with theatre: "I feel naff standing there and bowing; really hate it.") His short film career describes a perfect upward curve. When they filmed Privates on Parade, the role he thought he'd made his own with the RSC went to John Cleese. In terms of mega-wattage, his name was too dim a light bulb. Sadder but wiser, he then knew he'd never get to reprise his triumph in Shadowlands on screen. So he specifically did Demolition Man with Sylvester Stallone in order to ensure that, when they came to film The Madness of King George, they'd have heard of him in America. The Oscar nomination he secured was a near perfect way to announce his arrival in film at retirement age. Only the ceremony itself made him "very uncomfortable. I really hated it".

This month he's going back to Hollywood to film Big Brass Ring, a low-budget movie from a script from Orson Welles's bottom drawer, which was too hot a political potato when first drafted. "It's sort of Citizen Kane, only in a political field. Christopher Walken is playing the lead and I'm playing a sort of Harvard professor mentor type, the part Welles wrote for himself."

Already, there are signs that the script-meddling that bedevilled Demolition Man may be recurring. Hawthorne recalls how, under Stallone's aegis, the film he had agreed to do changed shape. "Gradually all the background stuff was being eroded and they were opting for the action stuff, so any depth of character or any intrigue that the character might have had started to evaporate. And there's nothing you can do about it, because they're very powerful. I'm not saying Christopher Walken will do that, because I've never met him. But certainly the script has altered since he's been on board. He's got together with the director and said, `I want a few changes.' I think it's actually improved a lot." He would say that too, wouldn't he?

`The Fragile Heart' is on Channel 4 on Wednesday, 10pm