Angelina Jolie and Brad Pitt
Angelina Jolie and Brad Pitt appear at the world premiere of "World War Z" in London Sunday. Pitt's new film is due in U.S. theaters June 21. Reuters

Angelina Jolie made her first public appearance with Brad Pitt on the red carpet at the world premiere of his new film “World War Z” since she underwent a preventive double mastectomy. The Oscar-winning actress was diagnosed with a BRCA1 gene mutation and reportedly had an 87 percent chance of developing breast cancer before she opted for the surgery.

Jolie has been widely praised as brave and heroic for going through with the surgery after she made her announcement in a New York Times op-ed piece titled “My Medical Choice.” She lost her mother to ovarian cancer at an early age and didn’t want her six children to suffer from the same kind of loss.

Her life partner Pitt has stayed strong by her side throughout the ordeal, telling reporters he was proud of the decision she made. While at his movie premiere in London Sunday, he told E Online he wasn’t surprised about how open Jolie, 37, was about her double mastectomy.

“That’s who I fell in love with from the very beginning,” the 49-year-old actor said. “The person that you see now is the person that I’ve always known and she’s heroic and incredibly strong and will attack any problem head-on and make it work.”

An E Online reporter hinted that having a partner like Pitt must help her to be strong, and he quipped back, “Well, I think so, I like to think so.” Pitt added with a smile. “We’ll see what she says.”

During the movie, Pitt gives an impassioned speech: “If you can fight, fight. Help each other. Be prepared for anything. Our war has just begun.”

Apparently, some of his real-life experiences with Jolie could have manifested in the movie. “We were writing it as we were going through those times so maybe, maybe,” Pitt said. “I didn’t even think about that. I’m sure it informed it in some way.”

“World War Z” hits U.S. theaters June 21.