Is there life after mum blecore? For Greta Gerwig, the mumblecore It Girl, there most cer tainly is.
On Friday, her foray into the mainstream, “Greenberg,” opens. It’s directed by Noah Baumbach and co-stars Ben Stiller.
That’s a big change from her low-budget, improvised, shot-on-video mumblecore movies, like “Hannah Takes the Stairs” (2007) and “Baghead” (2008).
There’s no improvising on Baumbach’s sets (his scripts are written in stone) and there’s a lot of rehearsal time; and the budgets are relatively large.
How did this switch in style go down with blond-haired Gerwig, who agreed to have brunch with me last week in a Irving Place cafe? (I had peanut butter and jelly on a poppy bagel, she went for a chicken sandwich.)
“I’m not done with micro-budget films,” she said. “I love making films that way. But I might be done with entirely improvised scripts.
“Noah’s script was genius and all his words were perfect, and you didn’t have to change anything. All you had to do is act, which is a relief. But I do love tiny films.”
And how does LA, where the movie was shot, compare with Gerwig’s home, New York City.
“I don’t know if I’d live there [LA], but I did really love being there. But I also think that I was doing work, I wasn’t looking for work — which helped — and I was surrounded by all these great people who knew Los Angeles.”
Stiller stars as a neurotic mess named Greenberg who just got out of the nuthouse and agrees to house-sit for his brother, who’s going to Vietnam with his family.
The brother’s posh house comes with a backyard pool, a dog named Mahler and a helper — inspiring singer Florence Marr, who’s played with effortless charm by Gerwig.
Baumbach is married to Jennifer Jason Leigh, who has a small part in the movie. Her mother’s house in the Hollywood Hills, on the other hand, has a large part because that’s where the movie was shot.
“That’s the house Jennifer grew up in,” Gerwig reported. “They moved her mom out and they redecorated it.”
Florence’s modest apartment was built on a soundstage, “but it was based on an apartment in Culver City.”
Gerwig used to live in Brooklyn; now home is Chelsea. “After the market crash, Manhattan apartments got cheaper; so I took advantage of our terrible economic state to upgrade apartments.”
Gerwig and company traveled to the Berlin Film Festival with “Greenberg.” She gushed over the festival premiere of “Shutter Island” because Martin Scorsese and Leonardo DiCaprio were sitting behind her.
“I was less engaged with the movie than I was engaged in the fact that Leonardo DiCaprio was sitting behind me,” Gerwig, 26, confessed.
“My 13-year-old self had the biggest crush on him.”
V.A. Musetto is film editor of The Post; vam@nypost.com