But unfortunately, when she walked out of the salon, "I looked like a mushroom—really. You should have seen it," she tells Playboy with a laugh that echoes around the room. Luckily, Milans is friends with fellow Spaniard, model and wife of Thor (a.k.a. Chris Hemsworth) Elsa Pataky. Pataky told Milans she needed to see her hairdresser, and the result proved to be something like magic when she showed up for the mystery audition.

"I didn't know who I was reading for, or what character," Milans says. "I walked in, and there was this lovely girl sitting behind the table. She stood to greet me and then sort of took a step back. And I'm like, 'Oh, do I smell? Do I look terrible?' And she said, 'No. Sorry. You just look so much like the character.'" From there, Milans read the two sides featuring bits of dialogue from the script, thanked her auditioner and left. A few weeks later, she learned she would be starring in Shazam!, DC Films' next big movie for Warner Bros. that hit theaters earlier this month. Pataky even chided that Milans wouldn't be going to the Thor premieres anymore, now that she's starring in the major Zachary Levi-led blockbuster for Marvel's rival.

Going back and forth between The Pier and Shazam! would be exhausting to mere mortals; Milans had a blast. "Flying to Toronto to have six kids and wear flats, after playing Katia, was fantastic," she says. "I learned I could do both. I can be the caregiver and a loving mother, and I can also be a sexy vixen that can transmit a lot of comedy. It was fun to play both sides of the spectrum at literally the same time.”

In Shazam!, Milans plays Rosa Vasquez, the compassionate foster mother of six children, including the title superhero. During the film's Toronto shoot, she adapted to the role of motherhood with a little help from karaoke. "We spent quite a lot of time together," she says of her on-screen kin. "The one thing that I was very adamant about before we even started shooting, was that I wanted to spend a lot of time with Cooper [Andrews, who plays Rosa's husband, Victor] and the kids. Yes, they're actors, but if you hug a 10-year-old for the first time, it's going to read on-screen."

So, Milans would throw waffle-making sessions in her apartment. They'd sing Mona and Frozen tunes together until the family became second nature. It all culminated on Milans' birthday, when she took the entire cast to karaoke. The actress—who has been around music her entire life, including lengthy violin lessons that began at age 3—wouldn’t divulge who was the best performer, but she did reveal that child actress Faithe Herman (Darla Dudley) was "kidnap material."

"We felt like a family from day one. I think that's the magic we made," Milans says. "That's why I do what I do. It's to touch people's hearts and to make them feel good about life. There's so much crap going on in the world right now. If we can bring empathy and love and support and hope to children, children that aren't wanted, aren't loved or don't have a family—that's a pretty great mission to have."

For Milans, who's also known for roles in last year's indie film Asher and in 2014's Jessica Chastain-starring The Disappearance of Eleanor Rigby, fostering remains an important mission that's close to her heart. Growing up, she would work with her mother and a local group of nuns to help disadvantaged youth. She remembers one young man whose mother was sick and dying. His family was poor, and he had four siblings to help raise. But after making it through that turbulent childhood, the young man grew up to study International Law in Germany. Milans sent him an email to tell him about Shazam!, and he wrote back, “The reason why I'm doing what I'm doing right now is because you and your mom never allowed me to think that I couldn't dream. I was so innocent that I wasn't aware of my limitations.”

Milans tears up, but her little laugh—light, sweet and full of hope—peeks through. “If you can do that to any child, whether it's with this movie, or whether it was actual fostering, or whether it was mentoring—imagine the goodness you can do to a kid's life," says the actress. "It's incredible."

Following the huge success of Shazam!, Milans is charged up to continue telling stories that matter, possibly from the directing chair as well. She's excited to work on original projects that feature empowered women, and is particularly intrigued by the prospect of bringing the realities of war to the screen. "We forget that during war, the people most affected, 100 percent, are women and children," she says. "We're used to seeing grandiose films and projects and TV shows about battle, but we don't have to disregard the stories of the women who are affected."