When it comes to Wong Kar-wai, attention should always be paid to the details.

The Hong Kong film director's characters often reveal a lot about themselves through the silences they share, or with a glance; and when we sit down to talk about his own experiences over the past few months, he is in a suitably reflective mood.

Wong begins by saying that when he decided to revisit the martial-arts genre for The Grandmaster, which was released in January and has since become the most successful box-office hit of his career (having taken an estimated US$50 million, and counting), he wanted his audiences to stop and think about what they were witnessing rather than be swept along in a swirl of action and excitement.

Those words appear to reveal something of what lies at the very heart of the man. Minutes earlier, Wong was standing outside the Normandy Barrière hotel, in the northern French town of Deauville, with his pocket camera out, taking snaps of the building's distinctive architecture. As flurries of guests came and went, he seemed - for a few moments, at least - intent on capturing the soul of this historic building, and tucking it away for posterity.

Wong is here for the Deauville Asian Film Festival, to present The Grandmaster to a French audience he has long held in his thrall, and his attendance has presented a rare chance to speak to the director away from the crowds, and offstage. In recent years he has been more inclined to offer himself for group questioning only.

"I am very grateful and very surprised," says Wong, of the reception his latest work received in his hometown. "The audience really responded to the film in Hong Kong. It's almost like revisiting this genre and I can see that the young audience is more interested in revisiting the cultural aspect of martial arts. The Grandmaster is not only about martial artists, it is about where Hong Kong came from.

"In the 1930s, 40 and 50s, there were so many immigrants moving to Hong Kong because of war on the mainland. All this new blood and new people created the Hong Kong we have today and I wanted people to think about that."

The film played to audiences who have been questioning what it means to be a "Hongkonger"; who are trying to discover what kind of future is being charted by their leaders - in the local government and in Beijing. For Wong, the film presented an opportunity to add to the discussion about identity.

"I am very proud to be a Hong Kong filmmaker," he says. "For the audience in Hong Kong today, I think they are extremely positive towards films that reflect on the identity of Hong Kong. They have seen a lot of films made in China, the co-productions, but they want to see something which can represent Hong Kong and give them the identity of this town."

When Wong first emerged from the TVB studios, at the end of the 80s, productions such as Days of Being Wild (1990) and Chungking Express (1994) focused their attention on the Hong Kong of the everyday, immortalised by such iconic scenes as Faye Wong riding the Central escalator. What audiences at home and around the world saw were images and characters that were uniquely of the city. Wong Kar-wai's acclaimed In the Mood for Love - which, in 2000, was nominated for the Palme d'Or at the Cannes Film Festival - was also very much about the people who inhabit the city, even though it was set in the 60s. But times have changed.

"When you come to Hong Kong, it seems like you are coming to a big shopping mall," says Wong. "If you live here, in Deauville, you will know the shops and you can say, 'This is the place I went to with my father when I was a kid. Or this is the shop where I met my first girlfriend.' But, today, in Hong Kong, there are no places like this. It's like all the places belong to LVMH or a big-brand label. So you feel like you are in a shopping mall.

"But you want to have your history, you want to have your identity."

Hence Wong's return to a genre he first immersed himself in for Ashes of Time (1994). And hence his decision to turn his attention to the story of Ip Man (played by Tony Leung Chiu-wai), the teacher who helped Bruce Lee hone his skills.

For Wong, the enduring interest in Ip - he has been the focus of a series of other productions over the past few years, from Wilson Yip Wai-shun's award-winning Ip Man (2008) to Herman Yau Lai-to's Ip Man: The Final Fight (2013) - is easily explained and the director expects there to be more attempts to tell his tale.

"When you look at the life story of Ip Man, he is almost like a reflection of the recent history of the republic," he says. "He was born in the Qing dynasty, a monarchy. He went from monarchy to war: the Japanese-Chinese war and civil war. Then he ended up in a British colony. A lot of films have focused on Ip Man, the character - his mastery, his skill, was he a good fighter? - and no film has looked at him from this perspective: what kind of hardships did he go through?

"If you don't understand where he came from you don't under-stand his greatness. The skill of wing chun was only for the elites but he transformed it to being for the common man, and this is important."

Wong admits, though, that after three years of shooting - which saw Leung break his arm twice and cast and crew battle extreme weather - it is highly unlikely he will return to the genre any time soon.

"I just need a rest," he laughs. "Actually, it's very hard to make a kung fu film because there have been so many kung fu films before. Most [of them] are about winning or losing, who is the better fighter, or revenge. I thought it was time to turn a new page and make a film not only about the skills but where the skills came from [and] the philosophy behind them.

"I think what made The Grandmaster different from the others is this film addressed one important aspect of the martial-arts world, and that's its legacy. It is something that the older generations want to pass on to the younger generations, that legacy."

Wong says he avoided watching too many martial-arts film before and during production ("As a kid, we were all exposed, at different stages") because his focus was on trying to expand what the audience knows - and has experienced - of the genre.

"There were different approaches to the fight scenes in this film but there was one principle," he says. "I wanted them to be as faithful to the style as possible. That means it had to be authentic. And that meant there couldn't be anything too crazy or that went against gravity.

"A lot of kung fu films [have] really been about violence," says Wong. "But, in a way, when you look at martial arts, the master will tell you that there is only one strike - that it will come so fast you won't see it. You are not going to keep punching for five minutes. But you can't shoot a kung fu film with every scene being just one punch. But for me there had to be a way to analyse this move," says Wong, who believes he successfully countered a reliance on extended violence by training the camera on individual moves. "How to prolong this one second, or this one strike, was our job - and it was very challenging."

For guidance on how to portray martial arts in this light, Wong turned to veteran fight co-ordinator Yuen Woo-ping - of Crouching Tiger, Hidden Dragon fame - whom he even convinced to act in a few short scenes. When it came to writing the script and staying true to the principles of wing chun, he enlisted the help of fellow filmmaker Xu Haofeng.

"You have to understand a bit about Xu Haofeng," Wong smiles, beginning an anecdote that reveals a little more about his own attention to detail. "He is now teaching at the [Beijing] Film Academy and he practised martial arts when he was very young. One day he felt he needed to see how good his technique was, so he jumped out of a building of the film academy, from the third floor. He wasn't killed, he was blocked by trees, but he had to stop working for two years."

Given neither Wong nor Xu appear to have mentioned this incident before, it's difficult to know whether the director is being metaphorical or not.

"During that time he practised Buddhism and I met him several times," he continues. "I also read the book he wrote on martial arts and found it very interesting. I asked him to co-write the film because he could provide a special insight into martial arts."

Xu has made two martial arts-based films - The Sword Identity in 2011 and last year's Judge Archer.

The Grandmaster opened the Berlin International Film Festival, in February, and Wong presented it here, in Deauville (last month). He was then scheduled to return to Hong Kong via Paris. All the travelling, he says, has given him a chance to explain first hand what he tried to achieve over the decade and more it took to take the film from concept to completion.

"We sometimes called this film Once Upon a Time in Kung Fu," Wong laughs. "That's why, at the end of the film, I used some Morricone tracks. It is like a homage to [filmmaker] Sergio Leone and [his score composer] Ennio Morricone; to their epics. Only a few films today are made in an epic sense. And 'an epic sense' doesn't mean the film has to be big. It is a film that makes you feel like you have lived through it. If you look at the films of Leone you have that feeling and that's what I wanted to do.

"I want my films not to be about one person but about a state of mind."