Ashton Kutcher and some of his co-stars were in London last night for the premiere of What Happens in Vegas.

Unfortunately Cameron Diaz couldn't make it, but Three's A Crowd had the opportunity to catch up with some of the stars, the film's director, and a few other familiar faces on the red carpet.

Compared to his grungy habits and very casual way of dress in the film, Kutcher looked rather polished in a relaxed outfit.

When we asked Kutcher how his character in the film compared to himself in real life, he jokingly responded, "Well, he looks a lot like me. I'm a really competitive person.

"That was probably my biggest draw from my own personal self because I can't stand to lose, like I hate losing. Like the last thing in the world I'd want ever is to lose."

But his competitive nature is softened by his sweet side, which shows in the way he treats his fans. When a girl loudly shouted her affection from the crowd, Kutcher responded with a similar: "I love you" right back at her.

The 'Nancies' from reality show I'd Do Anything made yet another appearance on the red carpet (they were at the Leatherheads premiere too.)

Talking of musicals we asked Kutcher how he felt about the genre. "I love musicals," Kutcher said. "I did Pirates of Penzance when I was in school and I liked it a lot, and I've done a couple musical episodes of things.

"I don't think I'm very good as a singer. I'm kind of like really a poor singer but if I ever got cast in one, I would do it in a minute. If I could do one, I think I would like to do Guys and Dolls."

Charmingly quirky Lake Bell, who plays Diaz's sidekick in the film, looked stunning in a short, red Marquesa dress that had a high neck with bunches of flowers on the shoulders.

She was a bit overwhelmed by the paparazzi and said: "It's interesting. It's different from LA. It's a little more." But she thought the whole event was fun. “It's lovely because I went to drama college here so to be in Leicester Square, I remember walking by and having the, 'Oh I hope one day...'so it's really wonderful."