In a film jammed with colourful characters, Jones steals the show as a spoiled actress who's both terrifically bitchy and deeply likeable at the same time. And she assures us that she's nothing like Gwen in real life: "There's no way that I am this character, even though I'm sure it's been an easy process to get there! She's just completely self-involved and there's nothing else that goes on around her that's of any interest. She is her own centre of the universe."

But she thoroughly enjoyed the chance to play such a prima donna. "I was having far too much fun playing her," she confesses. "And I just didn't want any iota of her being seeping into me as a person. She's just like, 'Go away!' When I wrapped production, she just had to go away and never to be seen again."

Julia Roberts plays Gwen's sister and assistant Kiki, who throws a spanner in the works by falling for Eddie just when Gwen thinks maybe they should get back together. "What I wanted to do with Julia, even though I play a very difficult human being-more difficult than anybody else you'd ever meet-I still wanted to have a sibling relationship with her. I've never had a sister, but my mother is one of, like, five girls and they love each other dearly, but they're able to do things and say things to each other that you would never say to anybody else. But because it's a sibling, you think you can get away with it. So I wanted to play with that," she says. "But my gosh, my character is just so into herself. It's just sickening!"

The most entertaining aspect of the film is the comic glimpse of what it's like behind the scenes in the movie PR business. "It's very different to the kind of celebrity-dom that I know of. But I think people have an interest in celebrities--'Are they really like that?' And this is, of course, a comedy based around that concept," Jones says, remembering one of the things that drew her to the film. "But it's also a wonderful insight into the drama and some of the crazy things that go on behind the scenes."