Rosario Dawson - The tough cookie with a soft centre

Rosario Dawson doesn't usually like the sassy women she plays. But in her latest film, Seven Pounds, she loves her character, a heart-transplant patient. What does that say about her, asks Kaleem Aftab

Aloudspeaker is almost a necessity when chatting to Rosario Dawson, who is playing Will Smith's belle in Seven Pounds.

I've met Dawson before and each time we talk I'm struck by her garrulous, feisty and fun attitude. The only trouble being that once the beautiful New Yorker is on a roll it's impossible to get a word in edgeways. Whenever one tries to butt in she simply carries on talking the talk and venturing off on her own iridescent tangents.

It's easy to be overwhelmed by the 29-year-old. We see Will Smith fall for her charms in Seven Pounds, and man-of-the-moment Mickey Rourke will be another falling under her spell when John Madden's long-gestating adaptation of Elmore Leonard's Killshot finally hits our screens. They're simply the latest in a list of hunks that includes Edward Norton (25th Hour), Colin Farrell (Alexander), Kurt Russell (Death Proof) and, er, Brian O'Halloran (Clerks 2).

Dawson specialises in playing hard-as-nails no-nonsense chicks, which makes her turn as Emily in Seven Pounds, as a taciturn patient awaiting a heart-transplant, a nice surprise. Although I'm even more surprised to hear Dawson say, "I fell in love with Emily. I have a tendency to play characters that I don't like very much."

I ask why she doesn't like the sassy characters that she's played so well since making her debut in Larry Clark's seminal Kids 14 years ago? After all, on first impression she seems to be the living embodiment of these characters.

Dawson replies, "It's fun to play those roles and there are very diverse variations of them, from Clerks 2, to Sin City, to Naturelle in 25th Hour, they're all different versions of the same types of woman, but they're not exactly women that I want to take home with me and introduce to anyone. They are interesting characters and they are in films that I really love. 25th Hour and its themes of choice and change are things that resonate with me, but the particular part that I was playing wasn't exactly a character I liked very much."

All these characters fit the cliché of being guys' chicks: gregarious, outgoing and sexy – the type of roles combined with her voluptuous looks that have made her a favourite of men's magazines around the globe. Quentin Tarantino really rammed this point home when he cast her as a thrill-seeking, toenail-painting girl gang member in his car crash Death Proof.

She goes right back to the start of her career to show how her on- screen persona is nothing like she is. Dawson wasn't pursuing an acting career when one day a young Harmony Korine spotted the then 15-year-old sitting on the stoop of her parent's Manhattan brownstone and asked if she'd be interested in auditioning for a film he'd written that photographer Larry Clark would be directing. The cinematic essay on high school children living in a New York frightened by the appearance of AIDS has Dawson play a promiscuous student.

She explains, "I've always been grateful for the parts that I've been given. The reality is that Kids was my first film, and when I did it people thought that I was like the character, and that is one of the reasons that Spike Lee wanted to hire me for He Got Game. When he met me and saw that I wasn't that person he appreciated that I had actually acted in that part, and he was really great with me and forced me to be stronger in my acting." She has a huge affection for Lee, but that did not stop the strong-willed actress turning down a part in She Hate Me, when a chance to work with Oliver Stone on sword-and-sandals yarn Alexander came up. She sees the positive side in continually trying out new experiences.

She has propensity to work with directors noted for their masculinity or at the very least their male-centred view of life. She doesn't disagree: "I just really like individuals, or individualists, I guess, and what all those directors have in common is that they're constantly challenging themselves and constantly re-inventing themselves and their particular view on things. A Spike Lee joint is a Spike Lee joint, as diverse as those movies are; when Quentin Tarantino works it's a Quentin Tarantino film; the same for Robert Rodriguez and Kevin Smith. I just love seeing myself through their eyes, being directed by them, because there is a particular way they see the world. It's really fascinating not to just go through the process of trying to put myself into a character's shoes, but also trying to glean what perspective of storytelling these different directors are coming up with. I like a strong director: I like being directed. I like someone taking me out of my comfort zone and pushing me beyond even what I see as my limits. Basically, it's working with people who are smarter than me and very talented."

She sees Seven Pounds as a pivotal moment in her career. It's a role she spent a lot of time researching — visiting trauma doctors, befriending a heart-transplant patient and learning the requisite medical lexicon, which she claims is like, "learning Klingon". During the unusually long rehearsal period, she was able to improvise dialogue and is proud that her suggestion that a Charles Aznavour number be used in a pivotal romantic scene was acted upon. It's the second time she's worked with Will Smith, although she's quick to make clear how different the atmosphere and working methods of this drama were to the comic caper Men In Black 2. She's pleased with her performance, and that's put her in a slight conundrum about what to do next.

"The character in Seven Pounds isn't a side of myself that I get to develop as much and that is one of the reasons why it's going to be very difficult to choose a film now," she says. "I'm seeking on building on this performance and not just going and doing something else for the sake of working. This is a chance for people to see a different side to me and maybe I'll be able to have an opportunity to play more diverse roles."

This search for roles is not just in the capacity of an actor. Her first film as a producer, rape-recovery drama Descent, played at the Tribeca Film Festival in 2007, and she has another couple of projects in the works, although last week she was disappointed by the news that British actor Robert Pattinson had to withdraw from the portmanteau drama Parts Per Billion because of a scheduling conflict with the Twilight sequel. In addition to Dawson, Olivia Thirlby and Dennis Hopper are still scheduled to star. There are also tentative plans to turn the comic book Occult Crimes Taskforce, which she co-wrote with David Atchinson, into a film.

On her multiple roles, she says, "I'm just keeping myself busy really. I really like being creative and it's really fun to do that. Instead of waiting for a job to be creative I've been trying to be creative on my own time. Look – I'm a New Yorker and I can multitask."

For such a proud New Yorker, she hasn't been doing much living in the Big Apple – ahe moved to LA three years ago. She responds, "Sunshine and palm trees aren't too shabby. I've also just bought a flat in London. I miss the British weather."

Indeed she plans to spend the next few months moving from LA to north London. She has been dating French DJ Mathieu Schreyer and regards London as a good base to see the world. However her pressing priority is to go to Washington to attend the Barack Obama inauguration. "It's really exciting. Especially as, at the moment, I've been really happy to take time out, which I don't think I've done in 14 years, and it feels really good that I can do that. In March or April I'll think about work."

'Seven Pounds' opens today