Interview: Michael Shannon, actor

But at six foot four with a giant noggin topped off by a brow that could serve as a balcony, he's tough to miss. Add in the fact that he has been nominated for an Academy Award (for Revolutionary Road), is currently starring in a bravura one-man show off Broadway (Mistakes Were Made) and as a vividly conflicted character in a big cable series (Boardwalk Empire), and his days of landing unnoticed are over. The table in front hangs out over the pavement, with a kind of proscenium above it, and passing Brooklynites couldn't help but stare: Oh yeah, that guy, the big, scary one.

Shannon doesn't seem to notice the looks, but he understands the shorthand, some of which derives from his role in Revolutionary Road. He played a hulking mental patient who bellowed truths amid the suburban banalities that overwhelmed the characters played by Kate Winslet and Leonardo DiCaprio.

"Plenty of people are onto the emptiness," he says at one point, "but it takes real guts to see the hopelessness." Dialogue doesn't get much darker than that, but it emerged naturally from Shannon.

"I'm just kind of odd," he says, settling in as the food arrives. "There are dark forces in the world, and if you pay attention to what's going on around you, you end up incorporating it into the storytelling. Maybe it's some aspect of myself that's coming through that people are seeing, that I am in fact a quiet psycho." His gentle, non-psycho smile suggests he finds humour in the typecasting.

"My dad used to say, 'You have to become part of the machine to beat the machine,' and there's some validity in it," he says. "But honestly, even when I'm inside the machine, you still see me. I stick out a little bit."

Shannon's industry fans include actor James Franco, who recently cast him as poet Hart Crane's lover in the short film The Broken Tower. "You can put Mike in almost any situation, and it feels genuine," Franco says. "He is the kind of actor other actors look to because he possesses great depth and mysteriousness. I think he can do anything." Then again, Franco also cast him as murderous necrophile in Herbert White, another short film he directed.

Shannon has been an actor since he was 16. After working steadily in Chicago's fertile theatre scene, he first came to prominence in New York when Bug, a play by Tracy Letts first staged in Chicago, moved off Broadway in 2004. True enough, Shannon played a deeply disturbed Iraq war veteran; but years later he filled the space at the Barrow with the gentle tones of the stage manager in Our Town, a folksy role that has belonged to actors such as Henry Fonda.

In movies he frequently appears in memorable small roles; his credits including Pearl Harbor, Vanilla Sky, 8 Mile and Before the Devil Knows You're Dead. The supporting role in Revolutionary Road was a breakout; he followed it up last year with a lurid, magnetic depiction of Kim Fowley, the band manager in The Runaways, cementing a reputation for bringing complexity to outsize characters.

He has had great freedom as a stage actor, but the pigeonhole as the big scary guy has been harder to wriggle out of in films. "It's not so much what others think you can do, it's what they want you to do," he says.

Not that he hasn't been willing to try. "I don't want to drop names, but a pretty famous director told me he was a fan, and that maybe, maybe, he was going to work with me in a romantic comedy," Shannon says, speaking in a mock-conspiratorial tone. "So I brushed my teeth and flossed and put on cologne and tried to look all bright-eyed and bushy-tailed, and, well, it just didn't work."

Even when he has tacked away from the dark side, it keeps pulling him back in. Perhaps it is not so much of a coincidence that it was Martin Scorsese, the director of the Boardwalk Empire pilot, who did the pulling, along with the series creator, Terence Winter, urging the actor to take the role of Nelson Van Alden, a prohibition agent who works the mean streets of Atlantic City.

"I was kind of seduced by the whole thing," Shannon says, rubbing his big head of hair as he recalls the meeting. "I thought, 'I'll be this paragon of virtue, and I'll be the one on the side of justice trying to take these bootleggers down'. Of course by the end of it my character turns out to be deeply flawed and possibly going insane. So I'm back to the same predicament."

Winter says he was less drawn by Shannon's ability to play people on the brink of losing their marbles than what he does for an audience. "Whenever he is on screen, you can't take your eyes off him," he says. "He can do funny, and yes, he can do scary and intense, but he is such a sweet person in real life that you'd expect to see some of that coming through in the roles he ends up with."

Shannon does have a remarkable lack of pretension, with an earnestness and sincerity that stands in contrast to his physical ostentation. During lunch, he dives into both the food and the discussion without the actor's reflex of making sure he looks and sounds just so. And back during his red-carpet tour as an Oscar-nominated actor, he showed up for everything to support Revolutionary Road, but in a tuxedo that looked as if it had landed on him from a very great distance.

"Michael is never going to be the fancy guy who spends on shoes and pants when he gets a little money in his pocket," says Guy Van Swearingen, former artistic director of the Red Orchid Theatre in Chicago. They met when Shannon began sleeping on his floor and working with him on shows.

Shannon was born in Lexington, Kentucky, and his parents – a social worker mother and professor father – split up early on. "The only time I can remember being in the same room with both of them was in a judge's quarters," he says. He divided time in high school between Kentucky and Illinois, playing parts in school plays and bass in a band called Jehovah's Suspects. He had an indifferent high school career and never had any formal acting training. Then he met Van Swearingen, and things moved quickly after that. "I started acting because I was miserable and crazy and wanted to be someone else, to run around and scream in front of people without getting in trouble," he explains.

Kate Arrington, his partner and fellow actor from the Chicago scene, says that part of the reason that he ends up emitting a lot of intensity is that it's there for the tapping. "When people say he is intense, they are speaking of one thing, and when I say it, I am speaking of six different things, and most of them are quite lovely to be with," she says. "You have to remember that he started acting when his life was truly unbearable."

These days it seems anything but. The couple and their two-year-old daughter, Sylvie, share an apartment in Brooklyn. And in Mistakes Were Made, he has got his arms around a taxing role that, Arrington recalls, often left him asleep face down on the ratty carpet in their rented Chicago apartment when the play was first done there. "I think he's learned to pace himself more during the run of the show in New York," she says.

Not that long ago Shannon delivered another night of motormouthed histrionics as Felix in Mistakes Were Made, but by the time he came out to the lobby after the show to see friends, he seemed to have shrunk. With a drab winter coat, stocking cap and backpack, he could have been the unassuming theatre rat who cadged a ticket off a friend. He chatted quietly, and then he was off for the subway.

• Boardwalk Empire began last nigh on Sky Atlantic.