By Lindsey Bahr
Updated October 18, 2013 at 04:01 PM EDT
Credit: Alex Bailey/Focus Features

Jude Law is a handsome man. He’s got the look of a wealthy, privileged playboy and has been cast as such more than a few times in his career. So when The Last King of Scotland director Kevin Macdonald started looking for a blue-collar guy to take on the lead role in his submarine thriller Black Sea, it’s easy to understand why he was hesitant to even consider the golden boy.

“I wanted somebody in their middle age and who was British and who could convincingly be a blue-collar guy,” Macdonald told EW. “If you look around Hollywood, there aren’t very many who look like that and certainly not stars. I went to see him thinking ‘well Jude Law is great, but he’s not really him.’”

But Law isn’t afraid of making an unglamorous transformation, whether he’s sporting rotting teeth for Contagion, yellowed fingernails for Road to Perdition, or an exaggerated receding hairline for Anna Karenina. He quickly convinced Macdonald that he could play the role of an embittered and unemployed former Navy man. Law adopted an Aberdeen accent, put on weight, built up his forearms and shoulders, shaved his head and let the stubble grow out and suddenly, he wasn’t the lithe Dickie Greenleaf anymore. He was a man you could imagine gathering a group of hardened Russian and British seamen for a trip to disputed waters, in search of treasure that might be sitting at the bottom of the Black Sea in a World War II era U-boat.

In Black Sea, Law’s character Robinson is definitely down on his luck. He’s been kicked out of the British Navy. He loses his job at marine salvage, too. But then, Robinson discovers a Russian U-boat that he believes to contain Russian gold sent to Hitler as a bribe — and he has his mission.

With Black Sea, Macdonald hopes to create a thrilling submarine movie in the vein of Run Silent, Run Deep (1958) and Das Boot (1981). “They’re incredibly tense, exciting films because of the claustrophobia and the sense that you’re somewhere you shouldn’t be. Like in space, if something goes wrong, you’re dead,” he said. They’ve actually been shooting on a real Russian submarine from the 1960s; Macdonald estimates that 80% of the movie is contained in those tight corridors.

Black Sea is also a reaction to the economy and the state of skilled laborers. “It’s about those people fighting back, the people who have been laid off and lost their jobs and blamed the big corporations and blame the establishment and the political system for the sh– lives that they’ve got,” Macdonald explained. “This is a way not only to get revenge but to get rich.” But it’s not as simple as some populist call to arms. Language barriers and greed come to the fore to threaten everything — as if Robinson’s plan weren’t complicated enough already.

Macdonald is still finishing the shoot for Black Sea, which is expected to hit theaters sometime in 2014. It fell a few weeks behind schedule after the water in the tank turned yellow — due to a chemical reaction between chlorine and memory foam, of all things — and the director’s crew had to drain 1.2 million liters of water, re-fill it, and re-heat it. “The perils of filming underwater,” he laughed. “Very annoying and expensive.”