All eyes were on the stunning Mad Max: Fury Road actress, 39, as she wore a low-cut black dress and matching coat as they partied at Craig's Restaurant in West Hollywood. Meanwhile, her soon-to-be husband, 54, looked dapper in a white button-up shirt and slick suit.
Us broke news last month that the couple secretly got engaged. They "decided to take their relationship to the next level," a source told Us of the pair, who began dating in early 2014.
Neither have spoken of the next chapter publicly, but their families are probably more than thrilled. In October, Penn's daughter Dylan, whom he shares with his second ex-wife Robin Wright, gushed about Theron at the Dsquared2 party in Hollywood.
"She's awesome," the model, 23, told Us. "She's great and they're amazing together. As long as my dad's happy, I'm happy for both of them." She added: "She's the only woman since my mom who can shut my dad up. The only woman! That is a f—ing challenge so…She's a powerhouse."
This will be the first marriage for Theron, who split from actor boyfriend Stuart Townsend in 2010 after nine years of dating. It will be the third for Penn, who divorced Madonna in 1989.
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