Lily James is really, really excited to breathe.

Since her breakout role as Lady Rose MacClare on Downton Abbey in 2012, the 28-year-old English actress has starred almost exclusively in a slew of high-profile period pieces—read: corset-confining—including 2015’s live-action Cinderella and BBC’s War & Peace. But with her latest role in Edgar Wright’s much buzzed-about film Baby Driver, James has finally arrived in the modern age.

“It was heaven,” James told me last week. “That waitress outfit was pretty tight, but I would breathe, which was a change. And it was great. I really wanted to do something contemporary, which felt like an escape. It was breath of fresh air to get into 2017.”

The highly stylized film, which focuses on a getaway driver named Baby, played by Ansel Elgort, in the midst of his final heist, is in fact just that—a breath of fresh air. “In a world of a lot of franchises and remakes, it's an original story and the characters are really unique; I feel kind of bowled over by Edgar and the movie,” James said. “When I saw the finished movie with the cast, I was like, ‘This movie is so cool, I can’t believe I’m in it.’ It feels really iconic and I think it could be a real cult classic, but it's mainstream enough that anyone and everyone can enjoy it. It’s got romance and action and comedy—it’s kind of genre-less.”

Lily James, one of the stars of the upcoming Baby Driver. Photo by Andrew Michael Casey for W Magazine. Hair by Adir Abergel; makeup by Kate Lee. Photo assistant: Will Casey.

In the film, which is in theaters on Wednesday, James played Deborah, a Southern waitress whom Elgort’s character quickly falls for, prompting him to leave a life of crime. “She’s a total dreamer,” the actress said of her Deborah. “She’s lonely, and yet she's optimistic. She kind of rattles around in this dead-end diner job with only truck drivers to talk to. You get the feeling that she’s a bit of a drifter and doesn’t know what she wants or what she’s about, and then this guy walks in and she kind of finds a purpose. She’s just a really genuine person.”

The role also saw the Brit ditch her usual posh lilt (see: period pieces) in favor of a twangy Southern accent. “I really worked on it,” said James. “I had this amazing voice coach, and I really focused on the character because being American isn’t just the voice. We really spent ages on it. Half of my family is American, so I do feel like I have American blood. But I’m still working on it.”

It helped that the filming was in Atlanta, where James and the rest of the star-studded cast, including Elgort, Kevin Spacey, Jamie Foxx, and Jon Hamm, spent four months last spring. “It was a really fun shoot,” said James. “The cast is insane, and they would bring boomboxes and play music on set. Everyone would sing. If I remember correctly, there was a lot of Michael Jackson.”

As with many of Wright’s previous films, including Shaun of the Dead and Scott Pilgrim vs. the World, music is integral—the movie comes off as something of a long-form music video featuring everything from The Beach Boys to Beck to Simon & Garfunkel. In fact, when James first received the script, it came with a playlist attached. “This little icon would come up and if you clicked it, it would play the song from that scene,” she explained. “I’ve done musicals before where, like Baby Driver, the music is key, but I’d never seen that before. I read it twice that way and then went to Spotify and made a playlist. And I still listen to the playlist.”

Another new addition to her listening rotation? Ansolo, Elgort’s side EDM project. “I hadn’t heard it before but while we were on set, he was writing new music and would play me ideas. He’s got this endless supply of music. Like our characters, we kind of hung out and talked about music.”

Lily James, one of the stars of the upcoming Baby Driver. Photo by Andrew Michael Casey for W Magazine. Hair by Adir Abergel; makeup by Kate Lee. Photo assistant: Will Casey.

As we talked, James was packing for a trip to the Glastonbury Music Festival, which took place over the weekend. “I just can’t wait,” she said. “I’m going to pull over, buy lots of alcohol and pour it out of the glass bottles into plastic ones because you can’t bring glass, toilet paper, and Wet Wipes, because that is how you wash for three days. It’s been a long time since I had some time to really let my hair down, and I love dancing, so I can’t wait to just dance around a field with my friends and my boyfriend… I’m going to go see Radiohead, and Liam Gallagher, and Laura Marling. I’ve always loved her. I feel really nostalgic because I spent most of my late teens listening to her, and when I put on certain tracks I can remember being in the halls of my university. I love the power of music in that way.”

And as for her festival style? “Usually I haven’t really gone into the full Glastonbury dress code thing, but this year I have. I was in Palm Springs and came across all of this old thrift and vintage stores and managed to buy some pretty cool and outrageous outfits. Which, of course, look really good when you are in the shop and then we got home and I was like, ‘Oh, I just bought lingerie. That’s not an outfit.’”

Sure beats a corset, though.

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