Interview: Wedding Belle; But Will Isla Fisher Find The Time To Get Sacha Baron Cohen Down The Aisle>

They are one of the oddest couples in showbusiness. He is the towering, 6ft 3in Sacha Baron Cohen and she is his fiancee, the tiny, 5ft 2in Isla Fisher. But as the Aussie actress says with a smile, “Height difference doesn’t generally keep people apart.”

Cohen is now a worldwide star thanks to his Ali G show and, more recently, the hilarious film debut of his outrageous Kazakhstan journalist Borat. Fisher, meanwhile, starred in the soap opera Home And Away but is only now making her mark in Hollywood in a big way.

The couple divide their time between homes in London and Los Angeles but, oddly enough, when they go out together it is 30-year-old Fisher who is recognised more than the higher-profile Cohen, 35.

“Well, he doesn’t have a big moustache in real life so he’s not that recognisable,” laughs Isla in her Beverly Hills hotel suite. “I think I’m more recognisable in some ways just because of my height and hair colour, but we’ve been pretty fortunate so far.”

Redheaded Fisher first hit Hollywood two years ago as Vince Vaughn’s off-kilter love interest in the blockbuster Wedding Crashers. She now has a host of projects lined up, but her latest film, out today, is the comedy Wedding Daze in which she stars alongside American Pie’s Jason Biggs.

It is the latest step on the road to major stardom for world traveller Isla, who was born in Muscat, Oman, to Scottish parents. As a child, she moved with her parents to Brunei and then Britain, before settling in Perth, Western Australia, when she was six years old.

“I definitely feel I’m Australian,” admits Isla, “and I have a laid-back attitude to life that is very Australian. I also love a good barbie! I just have to think of Bondi Beach and I get a strong longing to be there on the sand with the smell of suntan cream and hamburgers.”

Today, she is sporting a sparkling diamond engagement ring, but Isla insists she and Sacha have no plans to marry yet. “We haven’t set a date,” she confirms. “It’s been such a busy and exciting year.”

In fact, Isla has led a hectic life ever since she quit Home And Away. After a spell studying acting in Paris, she moved to London and worked with various repertory companies, while also briefly getting engaged to Darren Day. She was then cast in 2002′s Scooby-Doo, spending six months filming back in Australia.

Her profile was raised further in I Heart Huckabees, then came her scene-stealing splash as the sex-crazed bridesmaid in Wedding Crashers. Now, in Wedding Daze, she plays a waitress called Katie who gets a surprise proposal of marriage from Jason Biggs’ loser-in-love character.

“Katie is just someone who lives a really boring suburban life,” says Isla. “There is nothing going on. Emotionally she is engaged to this guy she doesn’t connect to and then this other bloke just walks into her life and proposes to her. She knows he is the one and they do everything so quickly. They get engaged before they’ve even had a conversation, they move in together before they even know each other and a lot of the comedy comes from the awkwardness of that.”

Isla also has two more movies awaiting release, Definitely, Maybe with Kevin Kline, and Hot Rod alongside Ian McShane.

“I don’t have any great strategy as to where I see my career going,” she admits. “I just read the script and have an instinct as to whether or not I like it. I’ve fallen in and out of love with acting in the past but at the moment I just really enjoy it. It’s the ultimate way for me to express myself.”

There are other advantages to being an up-and-coming new face in Hollywood, as well as the fiancee of a man whose movies make millions of pounds at the box office.

“Professionally, I’m able to meet with people that I wouldn’t have had the opportunity to get into a room with,” Isla smiles, before adding gleefully, “and I guess I’m given a lot of free clothes too!”