What impact has the success of American Beauty had on your life?
It gave me a lot of opportunities to do a lot of different things, which I was kind of surprised about. I thought I'd only get offers for very sullen, depressed teens, but actually the opposite happened. A lot of people put emotions in Jane that maybe weren't even there. They took her to all the extremes: they saw me as being someone very sweet and innocent and young to someone who's very mature and old. So it was a great range of projects that I got to look at. It just became the film that took me from kids roles to adult roles.

It allowed you to draw a line under your career as a child star.
Yeah, it became that thing to go further, to make that change from kid to adult.

What were some of the offers that particularly surprised you?
Actually this one. The gamut of emotions was so broad and there were so many layers and facets to Liz that I was really surprised. I thought,' Wow, they watched American Beauty and thought that I might be good at this? What?'

Maintaining Liz's ambiguity must have been the real challenge of this role.
Actually the real challenge was trying to figure which one was the real Liz. At first I had broken her into three characters but then at the end of day I thought, 'No, there's really about five here'. A lot of the time she's about two or three of them in the same moment. So for me the challenge was first off, trying to find out who is the absolute real Liz. I came to the conclusion that the first time we ever see her, when she's just come out of the hole and has a little scream, is the only real Liz that there is. The others are kind of degrees of her. So every day it was a battle and a struggle to try and decipher how much you wanted to tell the audience, how much you wanted to convey to the audience. I mean if you wanted to tip them off here, giving them a little side glance that might make them wonder there, and also trying to figure which one of them am I today.

Is she really in love or is it just a crush?
Throughout shooting the film I maintained the she was genuinely in love. Then everyday we would get subtle revisions from the writers, and one day we got a new scene completely. And it had this speech which I thought was one of the best speeches in the film. It was this speech where she says this way he never cheats on me or leaves; he doesn't grow old and all that. That's when I realised it wasn't love, she was just completely and utterly 100% obsessed. She wanted and needed - needed -- to possess him. She wanted to own him. Because if she could that would complete her life. She would be a complete person. She's already string, she's already smart, she's already on top of the school - owned it almost. Even though she wasn't popular within the in-crowd, she was a popular girl. She was up there in the higher echelons and she had everything except that one thing. And once she got that one thing, she would have been sorted.

Is some of her motivation loneliness?
Maybe. In some way, vaguely, it's almost a maternal thing. I think she had this image of them being together when they were very old and her taking care of him. You know, like 'Oh, little Mikey'. It's a very selfish, self-serving, self-possessed thing. It's like he's a pet or something. When she says, 'He'd never leave me', it's like he's her little puppy dog who would never run away. It's the idea of a much older woman to try and preserve his youth, and to visualise the situation from that point of view of he won't be old and decrepit now. That's only the thought of a 40-year-old woman, yet that's what runs through Liz's mind.

We talked last time about whether you were apprehensive about your growing celebrity and I wonder how that aspect of your life has changed. Have you become more closely acquainted with the pros and cons of it?
I'm not a well-versed person with regards to this topic because I grew up in the industry, and I think anything that happens, whether I shoot way, way up there or fall way, way below, wouldn't surprise me. Of course I'd be ecstatic or completely upset and depressed, but it wouldn't shock me. I wouldn't be shocked. And I think because of that, I just don't really even think about it. Sure there's certain cons as far as maybe a stalker watching you when you go out in public and things like that, but not even really because I love meeting genuine fans. When I go to a premiere or something and you go along a line and there's photographers, who are a bit of a pain I must say, but then there's these 13-year-old girls standing out there in the freezing cold, and you know they've been waiting all night with their little Disney autograph book in their hand, I just melt. I run to them because they're real fans and I'd rather sit and talk with them than wave to the photographers.

Some of the characters that you have played recently - Liz, Enid, Jane - have all been outsiders (less so, maybe, in the case of Liz). Do you relate to their being outsiders?
That's not the case with Liz. Definitely Enid, yeah. But not Liz.

We talked last time about your being an outsider at school.
That was my mood, actually. I wasn't really so much an outsider at school but right post-American Beauty I was kind of in that mode of kind of like, 'Yeah! I'm a rebel!' [laughs] I never got on with anyone, and kind of relishing in that. Which was an act, I gotta be honest. I did get along with kids and I still have some of my friends. I wasn't a cheerleader or anything but I did well. An outsider? That's an awful term [high-pitched giggle]. It's so lonely, it's not right. No one's an outsider. [her eyes get watery and her voice breaks a little] It's an awful term."

Nevertheless, you have given interviews more recently than mine where you still say that school was difficult for you.
Yeah, well, it was just a very definite kind of phase that I went through of kind of feeling that way. And then hearing it and thinking, 'Oh, it sounds very actorly of me,' I think I'll use that for a while. I just read it recently and I'm like, 'You know what? You're a lying tart, Thora'. [Laughs]

Is it odd then looking back at some of your other interviews?
Yeah, I mean a lot of things that you don't realise you're saying are suddenly in the written word, and to me the most powerful thing is the written word, because ever since I was a little girl that is how I'd memorise my lines. I actually saw the words in my mind and that would help me remember them. So to me it is the most powerful, the written word. Now when I see some of the stuff I've said I say, 'No, no, we're not going to go down that road again'. [laughs]

It's interesting because I was talking to John Boorman yesterday and he says that sometimes when he looks at his films he feels a stranger to them.
When I was younger and I watched my own movies, I did feel like just your average audience member. I was totally disconnected with the idea that that was me up there. I was 100% able to watch whoever that was that looked like me and was able to accept them as that character. Now, because I am actually paying attention to the work that I am doing, whereas when I was younger I was being myself and not really giving it any thought, now that I'm actually paying attention to the work I'm doing I actually make myself sick at certain moments. Not all the time. It's not like I'm retching and vomiting every time I see myself on the screen, but at certain moments or when there are certain things coming that I know were personal or that I had issues with or struggled with, whenever they're about to come onscreen I really seriously look away. I can't cope. It's really bizarre.

How do you feel about watching yourself in The Hole?
It's really uncomfortable. It's not fun. I'd rather shoot the whole film again. It was a stressful shoot, kind of, but I'd really rather shoot the whole film again than face some of it. That's not to say that I don't like it and I'm not happy with it, because actually I am proud of it, it came out well.

One of the things that really impressed me about your performance was the moment where he says he loves you and your face suddenly softens.
That scene was particularly difficult for me to shoot. I don't know how it is for the average audience member who's disconnected from the process of making the film, but I didn't believe him. But that was the point because he didn't, and he's not to be believed. He wasn't trying to put that across. So it's not an acting thing. It's just that I, Thora, knew that wasn't it, but Liz did have to think that was it. So I had to lie to myself and I knew that I was lying. It was a difficult scene.

The look, I felt, was one of desperation. She is so desperate for him to love her that it's like desperation.
I converted it to that because that's the only way I could believe it and believe what I was saying.

You're very critical about yourself onscreen. Are you very critical about yourself in life?
I should be more, probably. I think I put a lot of that critical energy into the creativity of it. Even when I'm shooting I'm constantly questioning myself: 'Am I doing enough work? Am I paying attention? Am I taking this serious enough?' Because to me that's where my passion lies. I allow myself to go as crazy as I want to when it comes to the work, but in the life aspect, for some reason I am unable to convert that and bring it into my everyday life. I must use it all up when I'm working.

But that's probably a good thing.
I guess so. We'll see how good it is.

You went to see Bridget Jones last night. Did you relate to her in any way?
It was a cute film, very endearing. Like those two guys, they were both very good.

I'm not sure what it means, but many of the papers are asking women whether they're for Hugh or Colin.
Unfortunately I would go for the Hugh I think. Whereas, when he says, 'You were meant for each other' doesn't apply to Bridget Jones, I think it would for some reason kind of apply to me. It would because I would be the one who would do something like that or understand or be able to forgive something like that. I would be like, 'You know what? You're right. Sure we're going to break up a lot, but we'll still get back together. It'll be OK.' [laughs] I know, it's sick."

No, it's relaxed.

Relaxed [laughs].

So what you're really saying is you're commitment shy.
No, not me.

A lot of child actors go off the rails but you appear very grounded.
Yeah, well a lot of child actors stop being actors because to begin with they didn't even want to do it. It was someone behind them propelling them along. That's what I remember. I remembers sensing that a lot of kids didn't want to be at those auditions whereas I was all for it. I was like, 'Yeah, bring it on'. But some of them I could tell weren't interested.