Relaxed, quietly elegant and tired after her recent round of interviews, Thandie Newton has reason to be enthused, both professionally and personally. She has a four-month old baby, her second child, and she is winning early Oscar buzz for her riveting performance in Crash. "It's nice to be talking to you about a film I actually love", she says, laughingly.

"Crash" , an ensemble drama delving into the cultural divide of Los Angeles, casts Newton as Christine, the beautiful light-coloured wife of TV producer Thayer (Terrence Howard). Christine is subjected to a humiliating body search by a bigoted cop (Matt Dillon), who is channeling all his anger for the lack of medical treatment his ill father is getting, into his job. Though the film explores the dark underbelly of Los Angeles, Newton says that she was attracted to this film far beyond her American character. "I was affected by the script on such a gut level, and I don't feel like it was (particularly Christine anyway) specific to L.A. or any country," the actress explains. "I think it's a dilemma which you could find yourself in, no matter where you're from. It's just about notions of betrayal, defending yourself, physical exploitation and all of these things, all of which I just felt very strongly about. But when I read the script as always, which has sometimes been a problem for me, I responded to the piece as a whole. I thought it was a really accomplished piece of writing, could be potentially a really dramatic and entertaining film, as well as having these very important themes, but not in an overbearing 'take your medicine' kind of way. I just thought that it really managed to be a lot of things all at once. I think I heard about the film about a year-and-a-half before it was shot, and there wasn't even a cast together, so it wasn't until we actually got around to costume fittings that I thought, 'Oh, my God, I'm gonna have to portray this character in these scenes, and that is heavy.' "

Newton concedes that she was initially wary, about shooting the film, in particular the tough, emotionally raw sequence, featuring co-star Matt Dillon. The actress says she was wary, "because it's just such a vulnerable position to be in as a woman. Also the scene next to the car wasn't sort of explicit the way it was written, I don't know why, so when it came to shooting that scene Paul [Haggis, director] took Matt and I aside and said, 'I need this to go very far. I just think that it needs to go to the limits'. When a scene isn't written explicitly you obviously project what you imagine would be good and right to have in that scene and I really didn't think it would be that much. So, it was very you know big deep breath and look at Matt Dillon and talk to him and, you know, 'you're great and we're just acting out roles' but it was very confronting," Newton concedes.

Newton says working on a film on such intense intimacy with an actor, may well have been a disaster had she and her co-star not gone along, admitting that such a relationship, in a scene such as this, goes beyond mere trust. "What if he'd been just a piece of crap, we hadn't got on, who enjoyed my discomfort or... or if I hadn't liked him and I'd enjoyed his discomfort. But more often than not in fact, I love the actors I work with. I can hear horror stories about people and have a great time working with them, so I think it's all really down to the situation and the atmosphere of what you're doing at the time. On this film, it was clear that everyone was doing it because they really felt committed to the material and we all have the same objective. It wasn't money or ego, everyone has four or five scenes, and you practically had to kind of drive yourself to set."

Newton has seen Crash once, with her husband, screenwriter Oliver Parker, at home on DVD. "We were both stunned when we saw it, and we didn't really speak much about it after. I think I need to see it again to gain more perspective." Married to Parker since 1998, the couple recently celebrated the birth of daughter Nico, their latest arrival. Motherhood remains a stark contrast to the kind of on screen intensity we see from her in the likes of Crash. "It means I can switch off very easily, and it keeps everything in perspective," Newton says. My work, emotionally, could have been the most powerful so far: where else do you experience extreme emotion like that? In life no way, but I experience extreme emotion like that with my kids all the time; that level of passion, love and desperate need to be with them and protect them. It's incredible." Newton, who tries to be selective when choosing a film, says it's a priority to spend as much time as possible at home with her family, "which is great in choosing material. I'm only going to be away from them for a certain amount of time so that the project has got to deliver on all these bases. Financially it's got to be not Crash - but lucky that was only like a week's work." Newton says that that if her husband is not working as much, she'll pick a big studio film, such as a Chronicles of Riddick. "Those decisions are all based on my life at home."

While Riddick didn't exactly generate critical raves, Thandie is unconcerned by perceived failures. "The thing is, I really think that I'm a good actor and I really value. So I can do something that I don't think is artistically that impressive or interesting and I still think that I'm going to be able to work again. I don't have that kind of fear, or think that a film is going to destroy my career, because the truth is, I've got more to give. It might be more difficult to get the next gig, but... I'm in it for the challenge, and it's never easy for me to get films because I don't do enough." Newton says, that as passionate as she is about acting, her career is not everything. "I'm not planning the right tactics. I think that you can do that, it's a real game that you can play, definitely, and you've got to do those magazine covers, get to those parties, meet and greet those people, but I just can't do it. I don't have that incentive, and I don't have the energy for that. I'm much more self reflective." Asked where that comes from, Newton pauses. "I think it's to do with having started out really young in this business and realising early on that my happiness did not lie with the business, quite the opposite. I had certain difficult times which I had to deal with which actually made me very skeptical about the film industry and as a result of that I looked away from it for my happiness and ended up meeting my husband. So in a weird way it's been a really good thing because it means I use the film industry as a pleasure for work and that kind of thing and it's not a pursuit to make me feel happy in my life.

Though 19, when she made an auspicious debut in John Duigan's Flirting, the now 33-year old, says she is pleased that 14 years later, Newton is still working. "I'm delighted that I am, because I think that there is a shelf life for people. You know, there are people, if you look at them, any actor, ebbing and flowing and disappearing - where are they now and I just feel like it's been a really lovely constant. I've done some things I'm really proud of and have worked, consistently and it's fantastic. I think that this is the best way it could be for me, and I've got two kids. I can't believe it, and I'm still able to work."

As to whether or not she can be persuaded to return in Vin Diesel's proposed continuation of the Riddick saga, Newton smiles, ever so sweetly. "I'm open to just about anything. 'Just about' anything."