The film sprang from a conversation Moore had with her close friend, writer-director Rebecca Miller. "Years and years ago," she recounts, "I told Rebecca that I knew this woman who had gotten divorced, and because of the kids she was still involved with her ex-husband. Then her current husband also had children, so it was very complicated. And she said to me, 'If I were to do it all over again, I don't know that I would get the divorce.' Because she still loved her ex-husband."

Julianne Moore plays a Scandinavian in Maggie's Plan

Both Moore and Miller identified with this idea. "Rebecca and I are both in these very long relationships with all the ups and downs," Moore says. "Sometimes, no matter what's happening, you look at him and you just have to go, 'Well, that's my guy.' It's that question if another relationship is going to be that much different than the one that you've invested all this time in."

To add to the texture of the film, Moore and Miller decided that Moore's character Georgette should be Scandinavian, which meant developing a style and an accent all her own. "My character is an academic, a fictocritical anthropologist," Moore laughs. "I wouldn't call her uptight, but she's formidable. But she's also not what she appears to be. I think a lot of her appearance is about being Scandinavian, which seems, well, different! But she's a very accomplished person. And doing the accent was a lot of fun."

Since getting her first break on the iconic American soap As the World Turns in the mid-1980s, Moore's memorable film roles have included The Big Lebowski, Short Cuts and Magnolia. She was also Oscar-nominated for Boogie Nights, The End of the Affair, The Hours and Far From Heaven before winning last year for Still Alice.

She says that switching to comedy for Maggie's Plan wasn't difficult. "I love comedy," she says. "I think the difference between drama and comedy is tone. One of the interesting things about this movie is that it's the world not as it is but as you wish it would be. So it's slightly elevated. That's what you're always trying to find when you're working on a comedy."

Watch the trailer for Maggie's Plan: