It’s evening in New York when I put the call through to the 49th Street rehearsal studio. The holding music that plays down the line is ‘Day by Day’ from Godspell.

The hippie Jesus lovefest of Godspell could hardly be further from the world of Kenneth Lonergan’s This Is Our Youth. Set in 1982, in a one-room apartment on Manhattan’s Upper West Side, it’s a play littered with illicit substances, cuss words, raging hormones and Frank Zappa records, with the undercurrent of angst you’d expect from a work originally titledBetrayal by Everyone. Since it premiered in 1996, a wealth of young Hollywood acting talent has been lured to the stage to play Lonergan’s three college-age slackers, including Matt Damon, Mark Ruffalo, Jake Gyllenhaal, Anna Paquin, Summer Phoenix, Casey Affleck and Freddie Prinze, Jr. This new production is no different.

Kieran Culkin picks up the phone while still shooing everyone else out of the room.

“Close the goddamn door! And get me some goddamn sandwiches!”

He’s joking – though it’s tempting to wonder if he’s already in character. A semi-regular stage actor, Culkin first performed in This Is Our Youth in 2003 at the Garrick Theatre in London, where the play had a young, devoted following of what Culkin calls the ‘superfans’. Back then, he played the weedy Warren. Now, Culkin has graduated to the role of the prickly, dominating Dennis.

“Actually from the moment I got off stage nine and half years ago, whatever it was, I just wanted to do it again,” Culkin says. “Most people I know that have done this play that have played one character are dying to play the other. All three characters are amazing and you just want to explore them all. I could keep doing this play forever, everywhere. I could tour with this fucking thing.”

Culkin also starred in the Lonergan-directed 2011 film Margaret, and Culkin’s enthusiasm for Lonergan’s work is clear. “He’s just a tremendously talented writer,” Culkin says. “But if you’ve read any of his work you’d know that immediately. Kind of ‘actor-proof’, I call it. You can have people who have no idea what they’re talking about but if they just do the punctuation correctly, they sound like geniuses.”

In a stroke of casting brilliance, Culkin’s co-star is Arrested Development and Juno star Michael Cera. He plays Warren, a character with some of the trademark Cera awkwardness and habit of knocking things over, but also a rebellious streak and heavy emotional baggage.

“To me, there’s nothing familiar about it,” says Cera. “It’s just beautifully written. Every nuance of dialogue for all of the characters. Every comma and every colon.” A smile creeps into Cera’s voice. “Every comma and every colon, as the saying goes. It’s just there for you: the dialogue and banter and rhythm feel so true of friendship, where you talk over each other, don’t really look at each other, and give each other a hard time. That’s what rings true to me.”

As Cera explains, it was Culkin who turned him onto the play in the first place, during re-shoots of Scott Pilgrim vs The World. Cera is a total newcomer to the stage – even high school musicals weren’t his scene. “But so far – I mean we did just start yesterday – it’s been really great. It’s just so exciting to actually be reading this play, with the other actors and with [director Mark Brokaw].”

Just don’t expect to see Cera on stage in five years playing Hamlet.

“We’ll see how this goes,” Cera says. “I don’t think that would be the most natural transition.”

Culkin and Cera will be joined on stage by Belvoir St Theatre regular Emily Barclay. Having performed in Chekhov and Oscar Wilde productions in 2011, and with a production of a Eugene O’Neill play later in 2012, Barclay says it’s refreshing to take on a theatre role that is thoroughly contemporary. She plays Jessica Goldman, an opinionated 19-year-old fashion student and the recipient of Warren’s fumbling advances. “These characters are all absolutely recognisable in what they’re going through,” says Barclay. “There’s something about being young that doesn’t change from 1980 to today, or 1960 to today. It’s always the same ideas and feelings and issues that young people are dealing with, come to terms with and navigating. It’s not easy to be able to create young voices that feel so authentic.”

For Barclay, a first-time visitor to New York, late-winter Manhattan itself is proving an inspiration.

“It’s amazing to be in the place where the play is set and be able to talk to Mark about being in New York in the 80s. To be in the city is just an incredible thing. It makes it come to life even more.”

The feature originally appeared in Time Out Sydney.