It’s a difficult image to shake: a young, blonde, fresh-faced young woman emerges wide-eyed and beaming into the Hollywood sunlight, with equal parts optimism and naiveté oozing out of her delicate pores.

The image is familiar to anyone who’s witnessed Naomi Watts’s star-making turn in David Lynch’s L.A. horror show Mulholland Dr. However, while her onscreen character found murder and mystery hiding behind the sunny veneer, the real Watts has had little reason to curb her optimism since emigrating from Australia.

Over the past five years, Watts has lived an actress’s dream, starring in challenging films that garner awards while also being golden at the box office.

So now, with almost complete freedom of choice, the Oscar-nominated Watts is selecting only the roles she passionately believes in. In Director John Curran’s domestic drama We Don’t Live Here Anymore an adaptation of two stories by Andre Dubus – who also wrote the stories on which In The Bedroom was based – Watts takes a supporting role as Edith, a suburban housewife who instigates an affair with her husband’s best friend (played by Mark Ruffalo). After her fiery turn in 21 Grams, however, it would have made sense for Watts to play Laura Dern’s meatier lead role as Ruffalo’s suffering wife.

"I always presume that I’m boring when I’m not emoting," Watts says of more subdued roles. "To be still and passive is scary to me." As such, taking on the role of Edith is just the latest challenge for the elegant thespian. "I know what it’s like to bottle emotion. But if I do, I just explode."

Though Watts disagrees with many of Edith’s decisions, she can analyze the complex motives of her character’s infidelity. "I really believe she was trying to get closer to her husband. [She] wasn’t reaching for a reaction or a cry for help – it wasn’t calculated. Edith has a lot of courage."

Watts has never been married, so her experience with adultery is limited. But infidelity is a subject she feels she understands. "I’ve been cheated on, and it’s horrible – you fear it. Anybody who hasn’t been cheated on is always fearful. That’s what makes this story completely human," admits Watts. "Inevitably, we have this horrible fear that we’re never enough. What can we do to be enough?"

Will this theme apply to her next project, Peter Jackson’s remake of King Kong? "Yes," Watts says, with a burst of laughter. "It’s about a three-way relationship.

"I’ve never done that kind of spectacle, fantasy film. And what better person to do it with than Peter Jackson?" she continues. "However, it’s still a very simplistic story about unrequited love; it’s very heartbreaking and dark."

Another project recently wrapped is the sequel to the highly profitable horror flick The Ring, directed by Hideo Nakata, who made the original Japanese Ringu films. "He understands the emotional content while being incredibly visual," reveals the leading lady.

Watts has reached the kind of stature as an actress where she can get a film made by simply showing interest. With We Don’t Live Here Anymore, in which she spent only two weeks filming her scenes, Watts is also working behind the camera for the first time as a producer.

"[Being a producer] is a great place to be, yes. I don’t know about with every film, but certainly with low-budget films.

"Back in the day, I organized an acting class with friends because we couldn’t afford to do anything fancy," says Watts. "It’s so awful to have to wait to be invited to act, so being a producer is just a way to connect with people who believe in the same things you do."