Greta Gerwig on the Grownups in 'Lady Bird'

I’m a big theater nerd. I like language that’s quotidian and poetic, casual but heightened. The emotions are real, but there’s something that feels too precise about it to be actually real. Lifelike, but different. There’s no hiding onstage, no cutting a performance together. Theater actors always show up knowing their lines inside and out; film actors have superstitions about being spontaneous. I’m not such a fan of that choice. I didn’t watch Homeland but saw Timothée Chalamet [who plays a Lady Bird boyfriend] in John Patrick Shanley’s Prodigal Son. I saw Lois Smith playing a blind seer onstage in John. Mind-blowingly good!

Smith, 87, plays another mother figure in the film, the teen star’s Catholic school mentor, Sister Sarah Joan.

I wanted someone to see Lady Bird, and see all of her — to not be taken in by her, to see her problems and flaws and still say, “I like you.” But not in a saccharine way, or a way that’s excusing what’s wrong with this girl, but like that Southern saying: “God loves you just as you are, but too much to let you stay that way.” It’s about that deep pleasure of being seen by someone completely. Lois has this empathy that emanates from her, not sympathy, empathy from having lived such a life. It’s palpable. The teenage girls just adored her. Between setups for scenes of her teaching class or doing skirt-length check, all the teenage girls would be around her talking to her because she has this quality of genuinely being wise.

Saoirse Ronan and Laurie Metcalf play a mother and daughter in "Lady Bird."

Merie Wallace/Courtesy of A24

Smith has stolen onscreen scenes from James Dean in East of Eden, Jack Nicholson in Five Easy Pieces, Tom Cruise in Minority Report, and Jon Hamm in Marjorie Prime — all movies as good as yours. What  Lady Bird  scene would  you put on a reel with those performances?

The one when Lady Bird is back from suspension, and Sister Sarah Joan knows she’s probably done  something  else deserving suspension. She tells Lady Bird something about herself and about love. We don’t cut to a close-up, but you have such a clear picture of her face, you feel like it was a close-up. It’s something about her voice and the way she says it that just resonates. She’s one in a million.

And which scene of Laurie Metcalf’s would you choose?

The scene that makes me cry reliably — and I’ve seen it hundreds of times — is when she comes into Lady Bird’s bedroom, hangs up a dress from the thrift store, picks up something off her bed and just looks at her asleep. It breaks my heart, all these invisible things that parents do that you’ll never know. You love this teenager, this crazy girl, so much that you don’t know what to do. You just watch her sleep.