NEW YORK - A close-up of Christian Bale's pot belly - in all its wobbly, hairy glory - fills almost the entire screen during the first frames of American Hustle, the new conman caper by director David O. Russell.
It prompts an audible intake of breath at a recent screening of the film in New York, where the audience is gobsmacked not so much by its girth - which is considerable - but the fact that once again, Bale has gone above and beyond what might be reasonably expected of an actor.
It is pretty obvious that he could just as easily have strapped on a prosthetic tummy - the bulge is so obscenely tumescent that it looks kind of fake, anyway.
Instead, the Oscar-winning star of The Fighter (2010) and The Dark Knight Batman trilogy (2005 - 2012) chose to gain the weight the hard way, putting on almost 20kg through a diet of doughnuts, cheeseburgers and other junk food.
Why go to all the trouble? The actor offered an explanation during a press conference in New York's Crosby Street Hotel earlier this month when the cast of the film, including Amy Adams, Bradley Cooper and Jennifer Lawrence, were asked about the allure of reinventing themselves for each movie.
"For me, it's studying people. It's nice," says Bale."Everybody dreams at night and tends to go a little insane. And that's acceptable, you know, because we're dreaming. To me, acting is sort of dreaming in a waking state because you get to study people and you get to go a little insane and be obsessive about something, and it's expected. And the more you are, the better it is. I find that very addictive."
As far as Bale's acting style is concerned, "insanity" might not be that much of an exaggeration.
The 39-year-old Briton is infamous for the lengths to which he goes in his movies, where he often plays tortured, brooding characters, such as the darker incarnation of Batman he created with director Christopher Nolan.
This frequently involves drastic and rather alarming physical metamorphoses - notably for The Machinist (2004), where he became deathly thin after dropping 28kg on a regimen of apples, salads, chewing gum and cigarettes in order to play an insomniac factory worker.
And once that film was completed, he had just six months to reverse this and put on 48kg for his next role, that of the muscle-bound caped crusader in Batman Begins (2005).
For American Hustle, which opens in Singapore this week, Bale makes himself over yet again, this time to play Irving Rosenfeld, a small-time crook who is caught by the Federal Bureau of Investigation and forced to help it run a sting.
As the slow-moving and bespectacled conman with a beer gut and an elaborate combover, the actor is virtually unrecognisable in this film, which is based on the real-life Abscam operations the bureau ran in the 1970s and 1980s to nab public officials on the take.
Even co-star and acting legend Robert De Niro, who has an uncredited part, did not recognise him when they were first introduced on set Russell reveals: "After De Niro met everybody, he said, 'Who's that guy?', and I said, 'You just shook his hand, it's Christian Bale.'