See Brad Pitt Back at Work Following Angelina Jolie’s Mastectomy Announcement

Brad Pitt is keeping calm and carrying on.

After his fiancée, Angelina Jolie, went public with the news that she underwent a preventive double mastectomy earlier this year, the 49-year-old "World War Z" star was back to work on Wednesday.

Dressed in layers of all black clothing – including some low-hanging pants that would be Justin Bieber-approved – and his favorite aviator shades, Pitt was photographed leaving Paramount Studios in Los Angeles. His long locks pulled back in a ponytail, he carried a black bag and a phone.

Just a day earlier, his long-time partner and the mother of his six children made the bombshell announcement that she had quietly undergone three months of procedures to complete a double mastectomy. The 37-year-old reached the decision after genetic testing showed she has a "faulty"BRCA1 gene, which greatly increases her risk of developing breast cancer and ovarian cancer. According to People magazine, she plans to have her ovaries removed as well.

In her New York Times op-ed piece detailing the medical procedure, Jolie talked about Pitt's unwavering support during the ordeal, noting he was by her side every step of the way. But Pitt had his own words of praise – for Jolie.

"Having witnessed this decision firsthand, I find Angie's choice, as well as so many others like her, absolutely heroic," he told London's Evening Standard on Tuesday, adding, "All I want ... is for her to have a long and healthy life, with myself and our children. This is a happy day for our family."

In a subsequent interview with USA Today, he talked about how they dealt with the situation as a family, sharing, "We set up our own little post-op recovery that became pretty fun. You make an adventure out of it."

And he had fighting words for breast cancer, saying, "My most proudest thing is our family. This isn't going to get that."

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