Design duo Tamara Ralph and Michael Russo dish on Angelina Jolie's head-turning white dress from the World War Z premiere in Berlin.

Splash News Online; John Rasimus/Startraks;Courtesy Ralph & Russo

Angelina Jolie made jaws drop across the globe when she hit the red carpet in a white peplum dress at the Berlin premiere of fiancé Brad Pitt’s new film World War Z. And if you’re still obsessing over the look as much as we are, we have a special treat. The designers behind the now-famous frock are sharing all the details with PEOPLE.

Tamara Ralph and Michael Russo (founders of the London-based brand Ralph & Russo) worked closely with Jolie to create the dress, for which the actress had a very specific request.

“She didn’t want to go for a full-length gown,” explains Ralph. “We wanted something very striking that wasn’t too overdressed, but wasn’t too understated. We wanted something modern, simple and elegant.”

After a string of black ensembles, the bright white midi with gold hardware at the waist seemed like an unexpected choice for the actress, but the designers (who’ve also made headlines for their work on Beyoncé’s World Tour costumes) explain it’s still classic Jolie.

“I don’t think it was a departure. Yes, this dress is a little bit different perhaps to other things, but the overall effect it gives is what she usually achieves on the red carpet,” Russo shares. “She always looks very glamorous and feminine.”

So how did Jolie feel about the final look?

“She loved it,” says Ralph. “She loves going through the design process and giving her feedback. It was nice to see it come to life. It looks exactly like the sketch.”

The pair also acknowledge that despite the actress’s recent double mastectomy, it was business as usual.

“We worked with her long before, and everything was as normal,” Russo says. “Her personality is so lovely, and it really radiates that beauty. Together, with the dress, it makes for an amazing overall image.”

Tell us: Did you love Angie’s white dress? What red carpet looks would you like to see the actress try?

–Michelle Ward with reporting by Simon Perry