In Heroes, a play translated from the French by Tom Stoppard which opens at Wyndham's in the West End this week, his role is no different. Gustave appears to be the leader of a trio of First World War veterans who make plans to escape from their retirement home in rural France. When he attempts to leave the grounds, however, he returns drained of his bombast. Hurt's stricken visage and shaking hands provide a theatrical kick to the gullet in a mostly humorous play.
But if, as Hurt, 65, says when we meet at the Soho Hotel in London, "everyone I've ever played has been flawed", perhaps one need look no further than his unhappy, disturbed childhood. Unhappy is one thing. But never before has Hurt spoken about the abuse perpetrated by Donald Cormack, the senior master at his prep school, St Michael's, Otford, near Sevenoaks in Kent.
This comes up early in our conversation only because we have a mutual friend who was at St Michael's with Hurt. I mention the friend as the trim and relaxed-looking actor settles into one of the huge zebra-skin chairs in the hotel's screening room. He told me, I say to Hurt, that Cormack used to remove his two front false teeth and insert his tongue in boys' mouths. "Oh yes, he used to do that," says Hurt, equably. "He thought it was a trick, like rubbing your face with his stubble."
I ask Hurt if it had happened to him. "It happened to me, yes. It happened to lots of people, I think." Actually putting his tongue in a boy's mouth? "Yes." What did Hurt make of it? "Human beings are very good at adapting to what happens," he replies. "You just accepted what was happening then. If it happened now he'd be behind bars. Without any question."
At that time St Michael's was a school of only 48 boys. There was no television, the pupils were not allowed radios, and, if a degree of quiet brutality was inflicted on their hapless offspring, the view of traditional parents was that such discipline was "character-forming".
The school's isolation meant that the boys had no other models of behaviour. "You had nothing to refer to," he says. "I don't think anyone believed that that sort of thing could go on at that school. It was incredibly high church and had such a high moral tone. Now it's co-educational, has 250 students and no boarders. But then ... Anyone who started off there has got a story in terms of life."
I ask him how this experience affected him. "Hugely, actually," he says. "I thought I swam through it all, but it must have affected me, because it's the only part of my childhood that I remember with absolute clarity. From arriving to leaving, there's hardly an event, the lifting of a desk lid, that I can't recall."
His next school, by comparison, was merely "ghastly" and "dreadful". All Hurt can remember from those years was playing Lady Bracknell in The Importance of Being Earnest and Mrs White in The Monkey's Paw. Acting has been Hurt's saviour, his means to express all that the unhappy little boy could not communicate, not even to his parents in their Derbyshire vicarage. He has won plaudits and acclaim throughout his long career, highlights of which include a petulant Caligula in I, Claudius, Stephen Ward in Scandal, Greta Scacchi's protector in White Mischief, an extraordinary performance as Jason Priestley's elderly admirer in Love and Death in Long Island, and numerous stage productions, not least a near-definitive realisation of the lead role in Beckett's Krapp's Last Tape.
"You want to act in order to show people that you are more than you appear to be," says Hurt, "that you have more to offer than had been allowed at school or within the vicarage. It's down to a desire for love, and all those, er, tricky things to talk about."
Hurt married for the fourth time in February, and declares himself to be "very fortunate" in "fantastic" domestic bliss. Is it calming him down? "It's not doing that, it's actually making me a much happier person. Wacky behaviour may seem like a lot of fun, but it usually isn't. It's usually the sign of a very distressed person looking for something they can't find."
For a long time, though, Hurt was almost as well-known for his distinctly "wacky" behaviour offstage as his brilliance on-screen. I ask him about a book awards dinner 10 years ago at which he gave a speech. Had he, perhaps, had a gin and tonic or three? (He was incoherent, the guests simultaneously enthralled and appalled by his ramblings.) "Aaah. Might have done," he says. "I have not behaved as I should have done on certain occasions."
Was his drinking due to the "distress" he mentioned before? "To an extent," he begins; and then considers. "But it could have been a complete error of judgement. It's not right according to the way people think now, that's for certain. Everybody's terribly aware of not being naughty now. Rather sad."
Hurt remembers different times. Working with Harold Pinter at the Arts Theatre in 1965, for instance. "A silver salver arrived in the middle of rehearsals," he says. "On it was gin and tonic, and ice and lemon. And it was 11.30 in the morning! The idea of that happening now - you couldn't think of it." People like stories about hell-raising actors, though. "They like the stories, yes. But you can't do it now. It's not the right climate."
More abstemious times mean that Hurt is unlikely to repeat one mistake: "I was doing a play in 1965 and one critic, Peter Lewis of the Express, gave it a panning. Those were the days when you'd leave the party at 4am to read the notices. So I read it, asked someone for a pen, and wrote him a note. 'Dear Mr Lewis, Whoooooops! Yours sincerely, John Hurt.' Then I foolishly sent it." Three weeks later he received a reply. "I opened this beautifully typed letter, which said, 'Dear Mr Hurt, Thank you for your short but tedious letter, Yours sincerely, Peter Lewis.'" Hurt roars with laughter. "Never write to a writer," he says. "Especially if you're a bit pissed."
Off he strolls into the Soho streets. "I wonder what the notices for Heroes will be like?" he says.
Born: 22 January, 1940, Chesterfield, one of three children of a high-church Anglican vicar.
Educated: St Michael's, Otford; Lincoln School; St Martin's School of Art; Rada. He won a scholarship to St Martin's, where one of the models he painted was Quentin Crisp, whom Hurt was later to play on screen.His big-screen break came after the director Fred Zinnemann cast him in the Oscar-winning film A Man for All Seasons in 1966.
High points: The Naked Civil Servant, 1975; awarded a Bafta. Midnight Express, 1978; nominated for Best Supporting Actor Oscar. The Elephant Man, 1980; nominated for Best Actor Oscar. Made a CBE, 2004.
Low points: Spaceballs, 1987. Romeo-Juliet, 1990. A Belgian film with a cast of cats.
Best known for: A grisly creature emerging from him in Alien, 1979.
Married: (for the fourth time) Anwen Rees-Myers, in February. Two sons from his third marriage.
He says: "I've done some stinkers. You can't regret it. There are always reasons for doing something, even if it's just the location."