If you want to figure out which film Christian Bale is working on next, a good place to start would be his accent. At the Berlin Film Festival earlier this year, he was brandishing a rather rich American drawl, not quite as thick as the one he sported for his role in 3:10 to Yuma but one that certainly ventured more Midwest than his role in American Psycho.
"It's a multiple-personality disorder," laughs the British actor, who appears in the Chinese war drama The Flowers of War, opening in UAE cinemas on Thursday. "I can never help it. If there's a character I know I'm going to be playing, I just sort of start doing it very slowly. Even I find it annoying. My daughter thinks it's very strange."
The accent could be something to do with Christopher Nolan's The Dark Knight Rises, due out in July and Bale's final outing as the most sour-faced (but awesome) Batman in film history. Or it might be a result of his character in The Flowers of War, Zhang Yimou's visually stunning epic that tells the story of a group of survivors during the "rape of Nanjing" in 1937.
Bale plays John Miller, a slovenly, alcoholic American drifter, "a refugee of the dust bowl", who finds himself in Nanjing tasked with performing a religious burial just as Japanese troops are brutally putting out the last remaining pockets of Chinese resistance in a city reduced mainly to rubble. "He's a jack-of-all-trades, somebody who has lost his belief," explains Bale. "But there's something going on there, he's covering something up."
Bale's character soon finds himself as the de facto father figure for a group of terrified children living in a foreign-run cathedral, among the few structures still standing across an apocalyptic landscape. "In a very unlikely manner, he comes to find meaning again, and a way to stop the running away that he's been doing for years. In the end, it's not about saving the girls, it's about saving himself."
Choosing such a production, the first real collaboration with a major Hollywood star in more than 100 years of Chinese film history, was considered an unusual move when it was first announced, even for an actor with a CV as diverse as Bale's.
"I would have been very envious if anybody else had taken the part," admits the Oscar-winning actor, adding that any language issues on set were quickly bypassed.
"Something very interesting I learnt working with Yimou is that conversation can only go so far. I've done so many movies where the talk is wonderful beforehand and I think that we're going to be making one movie and then you get there and you realise in the actually doing of it that no, it sounds good but, no, this is not the movie I thought I was going to be making."
With Zhang, the multi-award-winner behind such acclaimed cinematic masterpieces as Raise the Red Lantern and Hero, the experience proved far from the "sinking ship" Bale says he's been on before.
"I realised that we've got this communication but you push past it and come to understand through example what you're doing. And I came to have a far better understanding and communication and rapport with Yimou than I've had with many English-speaking directors."
Bale is keen to stress that his experience with "the people of China" was absolutely wonderful. "The crew were fantastic and they couldn't have been more welcoming," he says.
But there was one incident that is impossible to ignore. In December 2011, while in China for the world premiere of The Flowers of War, Bale went to visit the civil rights activist, Chen Guangcheng, who was under house arrest following his release after a four-year spell in prison. The famous 40-minute video from the accompanying CNN crew shows Bale being pushed and shoved by plainclothes guards as well as having stones hurled at him.
"Obviously, that's something that interests me greatly, but out of respect for my fellow filmmakers, I'd like to keep that separate," he says on the subject. "But I do feel like that does resonate with our story, looking at the courage of the individual spirit versus stronger opposing forces."
With The Flowers of War, Bale has, unwittingly or not, come a rather poetic full circle. Having made his Hollywood breakthrough at age 13 under the directorial guidance of Steven Spielberg with Empire of the Sun, based on JG Ballard's novel about prisoners of war in Second World War Shanghai and the first American film shot in the city since the 1940s, he has now returned to the country almost 25 years later for a drama of a very similar theme with Zhang. And in doing so, he has ticked off working with arguably both the greatest director from the West and greatest director from the East. In between, of course, he's added names such as Werner Herzog and Christopher Nolan to an increasingly bulging list of cinematic achievements.
Next up for Bale are projects with 2011's Palme d'Or winner Terrence Malick, with two films - Lawless and Knight of Cups - in the pipeline this year.
"After working on Batman, I was like: 'I need to go work with Terry now,'" he says. "He's one of my favourite people and favourite filmmakers. He's got fire in his belly."
The films, which will be "shot back to back", both star Bale, Natalie Portman and Cate Blanchett. Rooney Mara and Ryan Gosling also apparently appear in Lawless, with filming recently spotted at the SXSW festival in Texas and at Austin City Limits festival last year, where Bale was seen climbing on stage and playing the bongos along with the US indie outfit Fleet Foxes.
Predictably for Malick films, both are masked behind tight secrecy, leaving only guesswork as to whether characters reappear. "Well, there's the same director," laughs Bale of the connection between the two.
It might be a long shot given the filming locations, but to have a guess on Bale's next character it may be best to return to the accent game. Less than two weeks after Berlin, as one of the presenters at the Academy Awards, he had magically banished the American drawl for a bizarre cockney London twang.
Would Bale need to do a film in the UK to get his proper English accent back?
"To absolutely regain it, yes."
• The Flowers of War opens across the UAE on Thursday
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