Mutual admiration society

After years of digging each other’s work from afar, Lucas Hedges and Michael Cera are taking the Broadway stage together

LUCAS Hedges and Michael Cera play allies in Broadway’s “The Waverly Gallery,” but offstage, they’re practically a vaudeville act.

And while they’ve both been around — Hedges was an Oscar nominee for “Manchester by the Sea” and Cera appeared in TV’s “Arrested Development” and the films “Superbad,” “Juno” and more — they had never worked together until they were cast in Ken Lonergan’s drama, opening Thursday. What took them so long?

“We avoided each other,” Cera says. “At all costs,” Hedges adds.

Jokes aside — for now — Cera, 30, tells The Post that he took the role because Hedges was involved, while Hedges, 21, says he’s a big fan of Cera’s. Sitting together in Hedges’ dressing room, they seem like two old men on a park bench, obsessing over details while an intercom blares overhead.

“How do I turn it off ?” Hedges asks. “You probably have to rework the wiring,” Cera says. “I can get in there.”

They’d just come off the stage from their matinee alongside Elaine May, who plays a Greenwich Village art-gallery owner suffering from Alzheimer’s. Hedges plays her grandson and Cera, an artist. The play, based on Lonergan’s own gallery-owning grandmother, is both funny and deeply sad.

“I had a friend who came to see the show, whose grandmother went through this and recently passed away,” Hedges says. “She said that she had a lot of regret about how she handled the situation, but seeing us struggle through it gave her compassion for herself.”

Hedges, the son of writerdirector Peter Hedges, sees his Broadway debut as an escape from a jam-packed year of films: “Boy Erased,” about gay conver- sion therapy, will be out Nov. 2; “Ben Is Back,” about a young drug addict, is coming in December; and “Mid90s,” a drama directed by Jonah Hill, is out now.

“It kind of is great, because it gives me complete tunnel vision, and I get to forget that any of those movies exist,” says Hedges, as he fidgets with a foam yoga block.

Cera, who’s been on Broadway in two other Lonergan plays —“This Is Our Youth” and “Lobby Hero” — believes theater is the closest he’ll ever come to a 9-to-5 gig.

“It almost gives you a version of stability,” says Cera, who wed his longtime girlfriend this year. “It’s a very unusual [career] we’re in, when you’re not sleeping in your own bed, you’re not seeing your friends.” Although the two actors bonded during rehearsals and previews, they don’t always agree — not even about the weather.

“There’s something I find disturbing about the winter,” says Hedges, who grew up in Brooklyn. “I don’t mind it at all,” replies Cera, who lives in Brooklyn now but was raised in Canada. “You bundle up to go outside, and you just face it.”

They don’t agree on sports, either. Hedges love basketball and baseball and feels “an intense connection with” the Jets’ new quarterback Sam Darnold, while Cera couldn’t care less.

“I like playing sports,” he says. “I just never watched, and now I feel like it’s too late.” When he mentions playing squash, Hedges perks up.

“Dude, you play squash?” says the guy who ranked third in the nation when he attended high school in Brooklyn Heights. “We gotta play . . . I’ll whoop yo’ ass!”

One thing they both agree on is the privilege of working with May every night. The legendary comedian, writer and actress is 86, although Cera says she plainly considers age just a number.

“I love that she calls her daughter [68-year-old Jeannie Berlin] her ‘kid,’ ” says Cera. “That’s a good way to stay young.”

May, like Lonergan, is someone Hedges would love to collaborate with more, but he has some concerns.

“Sometimes, I think I’d give anything to work with this person again,” Hedges muses. “But I don’t know if they will want to work with me.”

And why is that, Cera jokingly wonders: “Because of your outbursts?”