Saoirse Ronan said she would 'only come out of semi-retirement' for “Blitz” director Steve McQueen

"The only way I would do anything else… is if, I don't know, Steve McQueen was making a film," the "Lady Bird" actress tells "Entertainment Weekly."

Saoirse Ronan wasn't looking for another project when Blitz came around.

In early 2022, the four-time Oscar nominee was in the midst of a three-month shoot in Australia for Garth Davis' Foe and had already committed to spending six months on The Outrun immediately afterward. "I'd been away from home for months," Ronan tells Entertainment Weekly. "I said to my agent, 'The only way I would do anything else after that is if, I don't know, Steve McQueen was making a film.'"

McQueen had recently completed his five-film anthology series Small Axe for Amazon, which included the courtroom drama Mangrove that costarred Ronan's husband Jack Lowden. "I'm such a huge fan of his, and I've always wanted to work with Steve," Ronan says. "When my husband worked with Steve, he would come home and say how impressive he found him and that working environment. So I said that that was the only way I was ever going to do it, sort of come out of semi-retirement."

Related: Saoirse Ronan is a mother on a mission in the first trailer for Steve McQueen's Blitz

Ronan was understandably surprised, then, when her agent procured a script for McQueen's next project: a World War II drama that follows a biracial boy trying to reunite with his mother in the chaos of war-torn London. "I got her call to say that she was interested in the role," McQueen recalled. "I was extremely flattered and very surprised because you never know — and how did she get the script anyway? But she's got a good agent, a very good agent. I was very excited."

Ronan was relieved to immediately establish a rapport with the 12 Years a Slave filmmaker during their first call. "I'm pretty sure you called me geezer, which I loved," she told McQueen. "When you were hanging up, you were like, 'Alright, geezer, I'll talk to you later.' And I was with Jack, and I was like, 'Steve McQueen's just called me a geezer. Couldn't be happier.' That was the beginning of our working relationship."

Related: Why Saoirse Ronan wanted to play 'a version of someone that has hurt me' in The Outrun

There was one problem, though: Ronan's character, Rita, spends a decent chunk of her screen time singing in both public and private, providing inspiring performances to her peers and gentle reassurance to her son George (Elliott Heffernan). Ronan, on the other hand, hasn't incorporated singing in any of her previous projects. "I thought to myself, 'Well, can she sing?'" McQueen says. "I thought, 'My God, she's this amazing artist, but can she sing?' I didn't know. She told me on the Zoom, 'I could hold the tune,' and I was like, 'Okay, you can hold the tune. You can hold the tune.'"

McQueen set Ronan up with a vocal coach to train and evaluate her voice. "I'll never forget that phone call I got from the singing coach," the director remembers. "She said to me, 'She not only can sing, it's only going to get better.' And I was just so happy. She said, 'Oh my God, this is going to be something.'" From there, Ronan's casting was a no-brainer. "I rang her and said, 'Look, this is amazing; I'm grateful that obviously you wanted a role, and yes, of course, it's yours. And that was it. That was the start of our journey."

Related: With The Outrun, Saoirse Ronan reminds us why she's one of the greatest working actresses

Ronan was thrilled by the opportunity to show off — and strengthen — her pipes. "I had so much fun — that was sort of my main prep for the character," she says, noting that she began working with a West End vocal coach over Zoom while shooting The Outrun and took a couple in-person lessons every week. "She was helping strengthen my voice through different exercises, and I just loved it."

Music has always been important to Ronan. "I'm not a professional singer at all, but I've always loved to sing, and music always just played such a huge role in my family life," she explains. "My mom loves to sing. It's such a huge part of how I express myself. So the fact that I got to actually work with someone on tapping into that to tell a story in that way was so wonderful."

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Growing up in a community surrounded by war stories also helped inform Ronan's performance. "There was a war in Ireland up until 40 years ago," she says. "So in the way in London and other major cities in the U.K., there is still such an echo of that time, and it's such recent history in Ireland — only a couple of generations in the past. It's something that I've grown up knowing about."

But Ronan focused on the story's emotional power more than historical specificity in her preparation. "Yes, it's set during the blitz, but that is the backdrop for a pure story of love," she says. "And I think I've always found, maybe because I started acting when I was so young — not that I've simplified it, but I've kept my focus quite pure. It's always been about, 'Okay, what is this relationship between this human and that human?' and build on it from that. So it really needed to be about the bond between a child and his mother, and that was my main focus the whole way through."

Blitz is now playing in theaters and hits Apple TV+ on Nov. 22.

This interview has been edited for clarity and length.