Amy Adams is most famous for playing wide-eyed innocents whose sunny outlook enriches the lives of those around her. Just think of toothy Brenda in Catch Me If You Can, heavily pregnant Ashley in Junebug and, of course, Giselle the misplaced princess in 2007's modern twist on a Disney fairytale, Enchanted. In fact, when Adams announced in December that she was pregnant by fiancé Darren Le Gallo, commentators expressed surprise that someone so "wholesome and pure" had ever actually had sex.
Hearing this, Adams looks taken aback for a second. "I'm not sure how I feel about that," she laughs awkwardly, looking perplexed as she leans back in her chair in the luxury of the Beverly Hilton hotel in Los Angeles. "Am I asexual? I don't present myself to the world like: everyone has to see my bits. But I wouldn't call myself prudish by any means."
The thing is, in this age of Megan Fox-style sexuality-as-a-weapon, Adams's attitude is actually quite rare, and that's what makes her attractive to men and relatable to women. "There are a lot of women out there like me," she nods. "I think it's something that's more fun to discover than to put out there."
It's this immaculate image that makes people so fascinated by the fact that Adams once worked as a scantily clad hostess for the notoriously trashy US restaurant chain Hooters. She's bored of talking about it now, having once said that her brief Hooters stint (she resigned after three weeks) had become her "entire press career".
Like many young actresses in Hollywood, Adams often had to contend with the assumption that it's impossible to be both cute and clever. Not that she ever felt as though she had to prove herself. "I never want to prove that I'm not stupid because, if someone thinks I'm stupid, it means I have the upper hand," she smiles. "It's not a matter of manipulation because I'm still myself, but it's amazing what people will say when they think that you don't really understand them. You can learn a lot about somebody that way. I once dated a guy who thought I was really stupid and I kept dating him because I was fascinated by it. He was very educated and liked to use big words and, although I may not speak like that, I'm an avid reader so I always knew what he was talking about. This was back when I was blonde and wore a lot of miniskirts. He actually used the line from Legally Blonde where he said I was more of a Marilyn than a Jackie O."
A natural blonde, Adams became a redhead five years ago on the advice of Junebug director Phil Morrison and has never looked back. Since then, she has twice been Oscar-nominated (in 2005 for Junebug and 2008 for Doubt) and has proved a big box-office draw, with Enchanted raking in £211m worldwide. Like Meryl Streep, alongside whom she starred in Doubt, Adams has the ability to flit between serious Oscar fare and frivolous romcoms such as her latest project, Leap Year.
In the film, she stars as Anna, an uptight American so exasperated by her boyfriend's reluctance to pop the question that she flies to Ireland with a plan to surprise him on his business trip and – it being a leap year – do the proposing herself. But, after an emergency landing leaves her stranded deep in the Irish countryside, she must enlist the help of a surly, stubbly, sexy innkeeper (bizarrely played by English toff Matthew Goode, of Brideshead Revisited fame) to drive her to Dublin. It's a classic fish-out-of-water comedy, with Anna torn between her initial contempt for the unreconstructed Irishman and her attraction to his obvious charms, all the while brushing the cowpat off her Louboutins.
She describes co-star Goode as "completely scrumptious – as cute as can be" – but admits they didn't click immediately. "I actually got really riled working with him at first," she explains. "He's very private in the way he works, while I'm very sharing. So I felt like I was chasing him all the time, which actually works really great for the characters. I could use that because it's the kind of thing that would make Anna crazy. She's angry the whole time and you can't create that. It's either there or it's not."
Adams is keen to disassociate herself from her character ("I grew up in Colorado so I'm not afraid of muck"), but she admits that she did relate to Anna's anxiety about getting married.
"Women have always wanted to get married," she smiles. "The difference is that now we feel that we actually have some amount of power to go after it ourselves, as opposed to sitting back and waiting for it to happen to us. I definitely have been in that position where I wanted to be in control. I want to make things happen for myself – but it doesn't always work like that."
So, were she not already engaged, would Adams have considered proposing to her boyfriend, like Anna?
"I would consider it and I did consider it," she laughs ruefully. "I knew that I wanted to marry him after about three dates, but it was six years before he proposed. In the second year especially, I really, really, really wanted to be engaged to him. But he was just taking his time. Eventually, I adopted the philosophy that he wasn't ready and I wasn't in a hurry, so I knew that it would be worth the wait. I trusted that it would happen eventually because we communicated our intentions with one another. It wasn't as if I was waiting in the dark. There have been cases when I have worked for a long time on films away from home and he has sacrificed so much to come visit me and keep our lives together. All I had to do was be patient and understanding."
Now that Adams finally has the rock on her finger, when's the big day?
"Well he actually proposed back in April," she smiles. "But I kept getting jobs so we had to keep pushing the date back. The irony is, now that I'm pregnant, I have time to plan a wedding. And, yes, I am very excited about it. We're getting everything ready for the baby now and, after this film, I'm going to take some time off." So, after a crazy decade, Amy Adams is finally going to be able to what she always dreamed of: get married, have a baby and do some serious nesting. After going through her own parents' divorce when she was 11 years old, does she still believe in happy endings?
"I don't think it's this sort of candy-coated dappled-lighting romance all the time," she says diplomatically. "But it isn't that abnormal to have a marriage that's successful. That's the reason I make films like this one. It allows you to believe in love and to have that fantasy."
'Leap Year' opens nationwide on 26 February