Brittany Murphy's 'Little Black Book'

The miracles of modern technology have made everything easier, even snooping on the ones we love, and Brittany Murphy admits she's guilty of that crime.

"I was at an ex-boyfriend's house once, looking for a vacuum cleaner," she says. "I ended up opening up a closet that I'd never opened and it was a shrine to all of his ex-girlfriends."

Murphy, 26, goes significantly further than that in her new movie, Little Black Book, scouring her boyfriend's password-protected little black book to look up his old girlfriends to find out why those relationships didn't work out.

As romantic comedies go, Little Black Book is rife with dark humor, and her character, daytime talk show producer Stacy Holt, could easily be called a psycho girlfriend who gets what's coming to her.

"Stacy's a good person. She's a smart person. She's a cool girl," Murphy says. "She just takes it too far."

A lot will depend on Murphy's on-screen appeal. After a breakthrough performance in Clueless nearly a decade ago, she's proven she can handle over-the-top characters, as the mental patient in the Michael Douglas thriller Don't Say a Word and as Eminem's girlfriend in 8 Mile.

Her recent stabs at comedy, however, in Uptown Girls and Just Married, have earned mixed results. Still, the $4 million she received for this new film, represents her biggest payday yet.

Little Black Book also features Holly Hunter, who, as Stacy's senior producer, puts a new spin on her popular performance as the neurotic newshound in Broadcast News.

Ron Livingston, best known from Sex and the City as the insecure writer who broke up with Carrie Bradshaw via Post-it note, brings an element of the hit HBO show to the film as Murphy's commitment-phobic boyfriend.

Kathy Bates rounds out the cast as the talk show host eager to exploit any sort of dysfunctional human into a ratings boost. Murphy's character does some exploiting of her own, using her role as producer to interview her boyfriend's ex-lovers — a bulimic model, an egocentric OB/GYN, and an insecure pastry chef, who just might be a better match for the man shes dating than Stacy herself.

While filming the movie, Murphy might have learned more about relationships off screen, having suffered two breakups, one with Just Married co-star Ashton Kutcher, whom she dated before he became involved with Demi Moore.

She later dated talent manager Jeffrey Kwatinez, and they got engaged in January. Four months later, they called it off. Both maintained the decision was mutual, even as gossip sheets claimed he was still in love with ex-flame Michelle Dupont, who is dating one of his clients, actor Adrien Brody.

Of her roller-coaster love life, Murphy admits it's been tough. "There was a breakup when we first started preproduction, which was the actor," she told the World Entertainment News Network, referring to Kutcher.

"We broke up a month into it, and then two, two and a half months ago, Jeffrey and I were engaged. And the timing wasn't right … Most importantly, we are friends now," she said.

"After heartbreak, there are different stages. First it's denial, then devastation. Then it's the tears, and then after that it's the chocolate. Then it becomes ambivalence and you get your anger, your fight up. Then you're back on your feet again, and you've learned, hopefully, a new lesson in life."

Murphy doesn't get to the chocolate part in Little Black Book, but she does get her just desserts.