NEW YORK -- The one thing Daniel Radcliffe always has to adjust to whenever he's onstage in America is how happy Americans are to see Daniel Radcliffe onstage.

The former "Harry Potter" star is consistently greeted by a burst of applause when makes his entrance on Broadway, no matter if it's a musical or a drama. The first time it happened was in "Equus" in 2008 and he had to stop himself from laughing.

"It's just something we are so unaccustomed to in England," Radcliffe says. "Obviously, it's a sign of being very liked and that's lovely. It's just something I don't think I'll ever get used to."

He'd better try: The actor is starring in Martin McDonagh's barbed comedy "The Cripple of Inishmaan," playing the disabled orphan Billy in 1930s Ireland who harbours an unlikely dream of Hollywood stardom.

First staged in 1996, the play is a typically potent mix of comedy and cruelty from the writer-director of the violent, witty movie "In Bruges" and plays "The Beauty Queen of Leenane," "The Pillowman" and "A Behanding in Spokane." This production, directed by Michael Grandage, debuted in the West End last year. Over here, it's at the Cort Theatre.

McDonagh's plays are littered with violence -- hands separated from limbs, people tortured upside down -- but Radcliffe says "The Cripple of Inishmaan" may knock some people off-guard.

"People who know the more brutal side of him will come to this play and be quite surprised by how moving it actually is," he says. "It's a beautiful play and a sad play and hopefully a play that will get people laughing despite themselves."

Radcliffe in person is unfailingly polite with no trace of ego. He's so sensitive that he poured himself into researching physical disabilities so he could be as true to life as possible. Though the script doesn't specify what Billy has beyond suffering partial paralysis, the actor decided his character has a form of cerebral palsy called hemiplegia.

"You're on dodgy ground a little bit when you're an able-bodied actor playing a character who lives with a disability. So I want to make it as authentic as I possibly can and by that I didn't just mean learning the physical, superficial mechanics of a disease and mimicking them," Radcliffe says.

"It's so much more than that and I think it would be very offensive to people to think you could just play a disability as if it's like putting on a hat."

The dark Irish comedy creates an interesting trio of Broadway roles for the former boy wizard. His mentally unstable teenager in "Equus" was followed by a singing-and-dancing con man in "How to Succeed in Business Without Really Trying" in 2011.

"I think that is quite a good cross-section of my tastes and personality," he says. "I think I've always had the idea that one of the keys to longevity is diversity. If you do the same thing your entire life, people either get bored of you or you get bored of doing the same thing. Either way, it's not good."

Grandage has watched the young actor throw himself into the part, complete with Irish accent and a paralyzed left side. With each role he does now, Radcliffe is erasing the one that made him a star.

"It doesn't surprise me that he is having such success shedding a world that we all know for all those years by approaching different projects in different ways with the same work ethic and going into such depth," Grandage says.

Broadway audiences -- regardless of their trigger-happy love of applause -- have a special place for Radcliffe, now 24. They took a chance on him after he emerged from eight "Harry Potter" films.

"At a time when everyone else was saying, 'Oh, he's only going to be Harry Potter,' New York just said, 'Well, let's see. Let's let him try to do something else.' That's a very cool thing to be given that opportunity."

Since "Potter," Radcliffe has mixed film and stage work. He's done the horror movie "The Woman in Black," the upcoming romantic comedy "What If," played Beat poet Allen Ginsberg in "Kill Your Darlings" and just finished playing mad-scientist's assistant Igor in Max Landis' pop-culture spin on the "Frankenstein" story.

Radcliffe says he admires the careers of Dustin Hoffman and James McAvoy -- character actors who often play leading men. That's why he liked Harry Potter, who represented a flawed, untypical hero.

"I like playing weird characters," he says, laughing. "I can only base things on the type of films I would want to see or the type of stuff that I would want to go to. That's how I make my decisions."