Living in Paris, hanging out with Justin Timberlake and celebrating femininity –it’s been a game-changing year for one of our favourite British exports.

Dusting away the flakes from her breakfast croissant, Gemma Arterton shakes my hand warmly and returns to the conversation she was having prior to my arrival… in fullblown French. Not clumsily recalled sentences from the GCSE syllabus; I’m talking meaningful, flawlessly pronounced, straight off an episode of The Returned kind of French.

It’s impressive since she only started learning four months ago – she signed up for an intensive course and credits her ‘musical ear’ for having grasped it so quickly – although the fact she’s currently living in Paris (we’ve taken the Eurostar over and are in a backstreet studio in the Latin quarter, not far from Gemma’s apartment) is undoubtedly helping.

“Everyone [here] is so sweet. When they hear the English accent they go: [adopts perfect French accent] ‘Oh, c’est trop charmant, c’est trop mignon…’ and they just think it’s really cute. But knowing I’ve got to shoot a film in French (Gemma Bovery) with French actors, it’s a pressure. I write in French daily.”

After spending the summer in Paris, Arterton, 27, will move on to Normandy to start filming, and you get the impression she is revelling in her summer exchange. “Every year I like to have something that I learn and this is the challenge this year – learning French.” Is she at an exciting crossroads in her life? “Yes,” she nods. “It’s such a transition now.” We’re not just talking geography.

Arterton is newly divorced, having split from her husband, fashion consultant Stefano Catelli – they married in 2010 – in February. So a new city and a new language is very much a new start; one that she’s giddily embracing.

Today the St Trinian’s and Quantum Of Solace actress is relaxed, full of enthusiasm, and loving the simplicity of our shoot – much more ‘her’ than spending hours in 30-degree heat wrapped up in cable knits and coats for a winter fashion story (her task the day before meeting us). Unselfconsciously throwing on a striped American Apparel T-shirt that she’s made into a bandeau dress by slashing the neck, she’s grateful we won’t be forcing her into multiple outfit changes. She’s very likeable – and refreshingly honest, even admitting to being embarrassed by some of her past work. I’m surprised by this, but the RADA graduate is someone who values the truth.

“It’s quite a tricky one if you’re an actor,” she begins, “because you obviously lie and you can’t be totally honest all the time otherwise everyone would know everything about you. So I’ve had to find a way of being honest without lying. That’s the only thing I expect from someone, honesty. I don’t expect anything else.”

With Arterton’s latest cinematic release Runner Runner, however, there’ll be no fibs required. Produced by Leonardo DiCaprio and starring Ben Affleck and Justin Timberlake, it’s a slick, glossy thriller-meetscrime- caper of the Ocean’s Eleven variety about a corrupt online gambling site in Puerto Rico, and will further cement Arterton as one of Hollywood’s go-to female leads. When she’s not hanging out in the Marais, that is…

Out of 10, how happy are you in both your professional and personal life right now?

In my professional life, an eight. In my personal life I’m a nine. I’m really happy. I document my life in various ways. I’ve written a diary every day since I was 15, three pages a day, and I’m so glad I’ve done it because I can look back on specific weeks and see exactly what was happening in my mind at that time and it’s really interesting in terms of how you progress. So, that’s a nine. I don’t ever want to reach 10 because then there’s nowhere else to go.

What was it like working with Justin Timberlake?

Most of my scenes were with Justin. He’s such a diamond. He is the loveliest, most down-to-earth, humble guy. I think he feels so grateful for everything and that’s a nice quality to have. After we made the film he was playing in London at The Forum in Kentish Town, and he said, “come down” so I was sitting in the box with Jessie, his wife [Jessica Biel] and I was like, “Jessie, you must be so proud” and she was like [adopts an American accent], “That’s my man!” He’s pure talent. And genuine as well.

And Ben Affleck?

He has so much confidence; he’s been on a film set all his life practically. It’s funny because when we made the film, Argo hadn’t come out but he was really proud of it; he showed it to us when we were there.

You’ve played some very sexy roles, while remaining likeable. How do you strike that balance?

I think it’s about not trying to be sexy. I don’t really know.

Do you feel confidently sexy?

Yeah. I don’t really think about it. I have a friend. She’s like this little yappy thing, and she goes, “Gemma, I’m just not sexy. How can I be sexy?” And I say, “Just don’t think about it”. People who I think are sexy, don’t think they’re sexy. My producing partner is the sexiest woman in the world to me, and she’s like, “I’m not”. She’s just had a baby and is like, “I feel like s*** and my boobs are down to my ankles.” And I’m like, “No, you’re sexy because you don’t give a f*** and you’re so confident”. That, to me, is sexy. So is a chick who can laugh at herself. I mean, sexy is whatever you make of it, but for me the haughty kind of bitch thing is just not.

You’re a champion of women’s issues. Have you come across The Everyday Sexism Project [everydaysexism.com]?

Yeah, my sister Hannah [also an actress and RADA graduate, 24] put something on it the other day. I think it’s brilliant. I mean, I’ve had it before; everyone’s had it. Someone put their hand up my bum one time. He went to squeeze my a*** but his hand went right up there and I ended up decking him. I know it shouldn’t have resulted in violence but it’s not acceptable. It’s an interesting time. Earlier, I was talking about these women who are singing things like “F*** me in the a***, bitch” and “P*ssies, nah nah, nah...” It’s good that they’re expressing themselves but it’s a bit extreme. Chicks are cool, we can do anything – we need to be given more opportunities. I’m proud of the fact that this year I’ve been able to express my opinion of body image in the right way. Early on in my career people would say, “You’re not skinny” and I’d see that as an attack. But now I’m like, “No, I’m not”. My goal in my career is to celebrate femininity.

You were saying earlier how much of a Lucy Mangan fan you are. Which of her Stylist columns have resonated with you?

God, I read them all the time. What I love about Lucy is that she’s hyper intelligent, but she’s also kind of a dick. Do you know what I mean? She takes the p**s out of herself. I remember one time she was like [adopts a posh accent], “I know everything about food. I know every calorie, I know every detail.” I can remember thinking, “I can’t believe you just admitted that,” but she was so honest and I love that about her. That’s why I like Stylist, because it is the contemporary, intelligent, cultured woman’s voice, and it resonates with me. It’s for the people I talk to in my everyday life.

Who else do you rate?

Marjane Satrapi’s a director who lives here in Paris. We made this film The Voices together and it was such an incredible experience for me. She’s just the coolest chick in the world. She made the film Persepolis that was Oscar-nominated and it’s about her life; she’s been through everything and nothing frightens her

What qualities have you inherited from your parents?

Hard work and grafting. My dad [Barry Arterton] often works six days a week and has done since he was 14. He works as a welder, a metalworker. My mum [Sally-Anne Heap] as well. She’s a cleaner and they have to work very hard because they don’t get paid very much, so that was just what we grew up with. If I was out of work, if I didn’t get any work as an actor, I wouldn’t be able to just sit around waiting for the phone to ring. I’d have to do something.

They got divorced when you were very young, how did that affect you?

It would be naive to say it doesn’t affect you, but we were lucky that they were very loving. And I’m very close to Hannah as well so we had this real unit. It’s like we’re twins or something.

Now you’re divorced. How does it feel to say that? Is there a stigma?

No. Mum said to me the other day: “Darling, you’re going to be like Elizabeth Taylor, you’re going to have hundreds of husbands,” and I said, “Oh well – that’s just the way it’s gonna be.” But, you know, obviously no-one gets married to get divorced, that’s just life. It’s the way it is.

So that hasn’t changed your outlook on marriage? Would you marry again?

At this point I’d say no, but I probably will [laughs]. Let’s be honest, I’ll probably have five others!

Is it harder in the dating game now?

Yeah. I would love to do online dating just for the laugh, just to see… but obviously I can’t do that. It’s tricky. It’s not like you can just go down the pub and pull someone. I mean you can totally do that, but I am a little bit more nervous, more guarded. That’s OK. I’m not in that zone yet.

You seem like a very passionate person. Does that come out in negative ways too?

I’m a Leo rising, darling, so yes, I’m very passionate. And impulsive. And fickle. I am quite fiery; in the last couple of years I’ve managed to tone that down a bit – I do yoga a lot.

What’s the last thing that made you cry?

Opening Night by John Cassavetes with Gena Rowlands. It’s devastating. It’s one of the most fantastic performances by a woman ever; it just got me for some reason. It’s about an actress who’s losing her s***! [laughs a lot]. I usually cry at kids’ movies more than anything, Good old Disney.

Earlier we were discussing the merits of The Great British Bake Off. What do you love about it?

It’s so English, so British. I love that people are so obsessed with it. People get so competitive but it’s about cake making. I mean, it’s such a sweet, cute, homely, comforting sort of old-school thing and everyone’s obsessed with it. The first time I really got into it was last year during the Olympics. At the same time there was all this Great British Bake Off stuff going on, and I was like, “Britain is so great! We’ve got the Olympics, we’ve got baking, and all this f***ing bunting everywhere”. I love it.

When it comes to cooking, are you a freestyler or a recipe follower?

I’m a recipe follower on desserts, as you have to be so precise. But with the main course and the starter I’ll experiment. I like that – it’s like a script. It’s like improvising on stage is fun and great, and magic happens, but with Shakespeare, you can’t veer away from that.

And then you get to produce something and people praise you for it…

For me, that’s the best bit. Every Christmas I make my famed marron (chestnut syrup) chocolate log. I’ve made it for the last five years. I make everything from scratch and decorate it with cranberries and things. When it comes out I’m like, “tah-dah.” Equally, if it goes wrong then I will consciously not show it to anybody. [Cooking] is a nice expression; something you make with love. I did this cookery course in Thailand and they were talking about making your own pasta. It was like: “Put your energy into the pasta – it makes it taste better.” [Things] usually taste nicer if someone’s put love into it.

Are you a perfectionist?

There’s a beauty in something that’s not quite perfect sometimes – the accident of it being a bit raw – there’s a real charm in that.

What’s your karaoke song?

Total Eclipse Of The Heart by Bonnie Tyler.

What was the last book you read?

I just read Madame Bovary, because of the film I’m doing

Runner Runner is in cinemas from Friday 27 September