Masked singer Little Women’s Greta Gerwig on Emma Watson, Meryl Streep, and more

This December, everything’s coming up March. Louisa May Alcott’s immortal quartet of fictional sisters will hit the big screen once again in Greta Gerwig’s adaptation of Little Women, and the filmmaker assembled an A-list cast to bring the American classic to life.

For her tomboyish heroine Jo and romantic hero Laurie, Gerwig reteamed with her Lady Bird stars Saoirse Ronan and Timothée Chalamet (both of whom appear, by the looks of the trailer, to have been born for these iconic roles). “I just adore them. They are just spectacular as live actors, and there is some true pairing between them that feels like [it’s] in the tradition of great cinematic pairing,” the filmmaker tells EW and PEOPLE. “I don’t know what they do — I mean, it’s magic. I direct them, but it’s all there.”

To play Jo’s elegant sister Meg, Gerwig turned to Emma Watson. “To me, [Watson] embodies everything that I was interested in, in terms of who the March women were,” Gerwig says. “She’s just smart. She’s on multi-governmental organizations that speak to the U.N., and she’s so thoughtful and present. She is way out there trying to do everything she can.”

Watson, an outspoken activist for gender equality, is best known for playing a witch and a princess who refuse to be limited by systemic oppression or social expectations — but here, she is not the obviously feisty Jo, but her much more outwardly conventional sister. “For me personally, Meg March is a character that is long misunderstood,” Gerwig says. “In terms of what [Watson] did with the character, she has so much open-heartedness and so much love combined with that much intelligence, it’s heartbreaking and potent. Because she’s absolutely herself with understanding the struggle of who that character is.”

The actress (and noted feminist book clubber) “would always bring so much to the conversation” from her extensive reading and research, Gerwig says. “She is all-in, not just as an actor, but as a mind.”

Also all-in was Laura Dern, who took her role as the preternaturally warm and patient Marmee very seriously. “Off-set, every single one of the girls actually did come to Laura with their heartaches and their problems,” Gerwig says. “Everybody had a good cry with Laura. She became this mother, sister, confidant person for everyone on set, which was a very beautiful thing to embody. She was a rock for everyone.”

Rounding out the family as the imperious, wealthy Aunt March is Meryl Streep, who was on board from the start. “She said she wanted to be part of it. She loved the book so much when she was a girl, and she thinks [it’s] so important, and she says, ‘Tell me what you’d like me to do,’” Gerwig remembers. “I was like, ‘Yes, ma’am.’”

Beyond that, the director won’t even attempt to adequately gush about the 21-time Oscar nominee. “Anything I say about Meryl is superfluous,” Gerwig says. “All the adjectives I have don’t touch it.”

Watch the first trailer above. Little Women hits theaters Dec. 25.

— With reporting from Kara Warner

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