Lookin' super old school!
Ben Affleck's looking old school!
The Gone Girl star is in Brunswick, Georgia filming his new movie, Live by Night, where the 43-year-old star is totally rocking the 1920s look!
An eyewitness tells ET that while on set, Affleck seemed "fairly happy" and seemed "to be enjoying himself."
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Affleck posted an Instagram of when the movie started filming on Wednesday, writing, "First day. First shot."
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Live by Night is a crime drama period piece based on the Dennis Lehane novel of the same name, which follows Affleck as an early-20th century mobster as he rises through the ranks.
Meanwhile, Jennifer Garner was back in Los Angeles with the ex-couple's children -- 9-year-old Violet, 6-year-old Seraphina, and 3-year-old Samuel.
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Affleck and Garner split in June, after 10 years of marriage. Despite this, the two were seen shopping together in Pacific Palisades last week. They've kept their relationship friendly for the kids, and continue to live in the same home.
Watch the video below.