IT IS SAID that CS Lewis wrote children's books, but in truth it is probably more accurate to say that he wrote books that children loved. The Chronicles of Narnia, if not on every actual shelf, can be found in the memories of any adult who ever had one of those magical books read to them. But there is an equally moving story beyond those pages and it is the latter part of the author's life that Shadowlands, the latest film from Sir Richard Attenborough, tries to bring into focus.

"Diana Hawkins told me that she had a script that I just had to read," says Attenborough. "She said it was the best piece of writing she'd seen. The following day we were recording some music for Chaplin and Tony Hopkins came in. I gave him the script to look at, just to see what he thought of it. I got home around 7:00 and spoke to Tony on the phone. He just said, 'You bloody devil! You knew exactly what you were doing, didn't you? I had to read it three times before I got though it, it's the most emotional piece of writing I've read.' So I asked him whether he'd be interested in the project. He said, 'Interested? I'll kill any actor that gets between me and this part!"' The ball was, indeed, rolling. Within a matter of days the money had been found to make the film. The project was green-lighted and preparations began. The story of Shadowlands, already both in award-winning stage play and BBC screenplay, deals with CS Lewis's involvement with an out-going American divorcee, Joy Gresham. She regularly corresponded with the author and finally met him on a visit to London, with her son Douglas.

She was, in many ways, the exact opposite of Lewis -- he quiet and considered, she louder and to the point. Their friendship grew, though neither would admit to their growing attraction. When Joy's divorce finally came through, they agreed to a marriage of convenience to allow Joy to remain in England. Shortly afterwards tragedy struck when Joy was diagnosed with bone cancer. Jack (as Lewis preferred to be called) and Joy finally admitted their love.

Working with director Richard Attenborough for the fifth time Hopkins is currently on the crest of a critical wave, coming off acclaimed performances in Howards End and Remains of the Day. The last few years have been good to him, winning an Oscar for his performance as Hannibal Lecter in Silence of the Lambs, and receiving a knighthood for his services to acting. But what is most noticeable is that for the last few years Hopkins has developed an inner calm to match the explosive talent that has always been apparent. His well publicized hell raising days are over, he has faced his own inner demons and emerged a better actor for it. "Anger's a kind of insanity really," he philosophizes, "I used to get angry at the slightest thing, but it's all role playing. I enjoyed playing the role of an angry man, seething and expecting justice and fairness. Life isn't like that, that's not how the world works. Over the years I've figured out that my philosophy is not to expect anything of people, expect nothing of life or the world -- then the likelihood is that you'll be pleasantly surprised.

"You're always going to get a few disappointments along the way, but my problem was that I was always setting myself up by expecting too much of people. I would expect loyalty, friendship, gratitude. But I learnt that people aren't like that. We're all treacherous, but of course we're all good too. It's just that we're unreliable. My attitude didn't change overnight, but when I began to not expect these things of people then amazing things started to happen. I suppose it's called acceptance."

Throughout his career Hopkins has been acclaimed as a superb talent, but for too long he was the exciting prospect, not the finished article. Born in the shadow of one of his heroes -- Richard Burton -- who came from the same small Welsh village, Hopkins worked at the National Theatre under Laurence Olivier in the '60s. Work on film and in television marked his efforts to make his break out of these shadows, and once the range of his talents became fully recognized he returned to the stage in a succession of triumphant performances, from M Butterfly to Pravda to King Lear. Sir Richard (now Lord Attenborough) has nothing but praise for Hopkins. "[Tony] reads the script a hundred times, a hundred and fifty times, and when he comes onto the floor he knows it absolutely backwards. But he improvises, he doesn't say the right lines right up to the point of the first take. That way he keeps it fresh, so he is actually saying those words for the first time. I think that this is the best piece of work Tony has ever done in his life."

In his selection of Debra Winger, who takes the role of Joy, Attenborough says, "There was a certain pressure to cast particular actresses, but I felt very strongly that Debra is not only a superb actress, but also possesses the personality that has a similar abrasiveness [to Joy]. Of course, Debra does have something of a reputation for being very 'difficult', so we did have a conversation at the start and she said she was only difficult if it would improve her work. She wouldn't swan off to her caravan between takes. All she cared about was making her character as real as possible."

Joseph Mazzello plays the young Douglas, in awe of the man who wrote the books he loves and disappointed in the reality of a totally normal attic and wardrobe. Cinema-goers will recognize Joey from his starring role as Tim, one of the kids caught in Jurassic Park. In that film he played the grandson of the park's owner played by none other than Sir Richard. How was it for Joey to work for him, rather than with him? "No, it wasn't really different," explains Joey. "The only difference was that this time he got to tell me what to do!" Though Joey obviously came to Sir Richard's attention on the Jurassic set, it was by no means certain that the young performer would be able to take the role. Stanley Kubrick had already decided that he wanted Joey for his next project. Thankfully, the timing of the projects and friendly negotiations paid off.

"Tony, Debra and I hated him..." smiles Attenborough. "At the age of nine, to know as much about acting as Debra and Tony... and not be spoiled by it! Away from the movies he lives the life of a perfectly normal boy over, away from Hollywood, on the East Coast. But the moment he gets on the set he's so professional. You can't talk down to him, he's insulted if you don't treat him like an equal!"

Remarkably unaffected by his success Mazzello seems a respectful, normal child whose honesty and simplicity transfers beautifully to the screen. In one memorable scene that he shares with Hopkins after Joy's death he was required to break down in tears, a difficult task that he managed to do on cue for four successive takes. "During the scene I just thought how sad I would be if my mother died," he explains matter-of-factly, "and that would be very sad. The most difficult thing about a scene like that one is that after it's over you feel very tired. "Joey's a lovely kid," adds Edward Hardwicke, who plays Jack's devoted brother 'Warnie'. "I think he's working with Meryl Streep now. Debra overheard him saying that he was off to do that film next and she asked him what he was playing. He told her that the role was 'some kid', and without batting an eyelid she said, 'oh that'll be a stretch for you!' She's very quick."

For a film that was by turns tragic and deeply serious there was a lot of laughter on the set of Shadowlands. When the cameras stopped rolling the laughter began, as Edward Hardwicke recalls. "Without question this was one of the happiest jobs that I've had," explains Hardwicke, a familiar face as Dr Watson in Granada's Sherlock Holmes.

"It's a very serious subject I know, but we spent the entire shoot roaring with laughter. "Richard creates a wonderful atmosphere on the set, and both Tony and Debra are very funny people anyway. It's actually a very good thing to do on a serious film because it relaxes everybody, and if you start thinking too much about the subject matter you could get really depressed." And now, in place of the prickly reputation that used to follow him around, Hopkins has earned a name as a bit of a joker on set, as Hardwicke -- who has known him for thirty years -- explains.

"Tony is very relaxed these days, he makes the whole thing seem so easy. Right up to the moment that the director says action he's telling you a joke, and because he's so laid back everybody else is very relaxed. That helps create a very good atmosphere. It's effortless, you don't feel any strain in what he's doing and I think that helps everybody. He's also a very charismatic man, the closest thing you'll get to a genius as far as acting is concerned."

Hopkins, as modest an actor as you will find, would never agree with that, and is noticeable in interviews for blithely dismissing his own efforts. He is certainly never one to mystify the actor's task. "The process of acting is really very simple," he says, "and what I've learned over the last few years is that the actor imitates the inner image of what he sees in the character. That's the way I approach it. And if you're relaxed and you enjoy the work you can improvise a bit, most acting is improvisation after all -- you don't plan every gesture. If you know your text well enough and you feel relaxed and you don't have someone screaming and shouting like a maniac then you can have a good time and start to look sort of natural. That's the essence of keeping it realistic." From the same kind of theatrical background as Hopkins, Hardwicke takes a similar approach to the roles that he plays, and admits that he only researched the character of Jack Lewis's brother very briefly. "I read a biography and got a lot of information from Warnie about that," he explains, "but really you do have to fall back on what's in the script. I remember seeing an actor who I admire enormously playing Stalin in a production at the National Theatre, he was quite brilliant, but he played the whole thing with this stiff arm. Afterwards I asked if he'd hurt himself but he told me that Stalin had a polio arm from childhood, he'd read it in a book. There wasn't a reference to it in the play, so everybody assumed he'd hurt his own arm. I always felt there was a lesson there. You can get influenced by things like that but they're really no help at all if they're not actually in the script."

It's a style that's in stark contrast to Debra Winger's whose approach involves deep and thorough research. And she is every bit the perfectionist that Hopkins is, which is un doubtedly the source of her reputation for being difficult. "To be perfectly honest I didn't know that Debra even had that reputation," Hardwicke continues. "It was only after we'd finished that Richard and Tony said about it, and everybody expressed their amazement because she was such fun. I've worked with several people who have strong reputations for playing up, but it's often because they're such perfectionists. They really don't like it if there's anybody incompetent or slightly unsure around them, it's then that they go for the jugular. That's generally because they themselves are very professional and very good at their jobs and aren't terribly understanding of people who aren't. It's always a little bit daunting to find a well known Hollywood star there in your midst, you do wonder if they're going to be difficult, but she wasn't at all."

Even Winger's very centred, determined course must have been a bit shaken when Douglas, Joy Gresham's son visited the set. "Douglas visited the set several times," Hardwicke continues. "It must have been strange for him I suppose, but he lived with the play on television and the stage for about ten years so it's not something that he was coming to cold. I asked him if he found it all a bit strange and he told me that eventually the fact and fiction become blurred and it was now hard to tell them apart." The screenplay for Shadowlands was written by William Nicholson who also wrote the original stage play. Sir Richard admits that he never saw the original play. "I was away for a majority of the time it was running in London and I deliberately did not see the BBC version until our screenplay was ready. At that point, it seemed sensible to take a look and see if there was any little thing that William hadn't put in that we could use from the original script."

With the unlikely romance acting as the film's central theme, Shadowlands also highlights the closeted life of an academic at Oxford in the '50s, with Joy raising more than a few eyebrows with her bluntness, incisive intelligence and -- horror of horrors -- femininity.

Hardwicke again: "That kind of closed Donnish existence at the University is very, very difficult to break into. She wasn't well received, which obviously comes out in the film. She was from a different planet as far as they were concerned, and I think it was very difficult for anybody to accept her at first, particularly Warnie. But of course Jack Lewis himself wasn't very popular there either because he was this well known celebrity, and they didn't like that. They didn't like anybody who moved in circles outside the university itself. "Before we started shooting we went to a party with some of the Dons at one of the colleges, Richard had arranged it, and I spoke to a young padre who had been there for a couple of years. He explained that he was still quite terrified because you really are being judged by everybody; the people you're teaching and the people who are your peers and colleagues in the college. "I can imagine that all those wonderful surroundings make for a terribly lonely place if you're not totally given over to that kind of life."

Without doubt Shadowlands is a powerful and emotional film and many agree with Sir Richard that this is Hopkins at his best. Even last year, the rumour was that the Welshman would have something of a double-whammy with both Remains of the Day and Shadowlands likely contenders for that golden little icon in more than one category. The next few weeks will decide if any Oscars will be heading our way again. Sir Richard is proud of his latest epic, but is philosophical. "After all, there have been many great films this year. Personally, I think Schindler's List will be up there on the night!"

And Hopkins, through everything, is the joker in the pack. The mimic, the wit, the one who can break up colleagues with an off the cuff remark -- it's a side of him that could scarcely have been imagined during his wild youth, but in terms of the quality of his work this change is paying off handsomely. "I'm very contented these days," he smiles, "but I've had to work for it. I know some people who just love misery, it seems to be predominant in the acting profession where it's almost unfashionable to be happy. If you're happy then it means you're very facile and rather shallow so therefore you can't be a serious actor, but that's a load of bull really.

"When I worked at the National Theatre and I went into the canteen and said, 'Morning!', it was like Dracula coming in. I'd say to people; 'Morning, how are you?' and they'd look at me oddly and say 'how are you?' I'd just reply, 'I feel on top of the world'".