After spending the weekend in Atlanta with Jennifer Garner and their three kids, Ben Affleck was back in Los Angeles on Monday with his buddy Matt Damon for the premiere of the new season of Project Greenlight.

Affleck, sporting a scruffy salt-and-pepper beard, walked the red carpet wearing his wedding ring. The 42-year-old actor rocked a blue suit and smiled for the cameras before entering the premiere.

While Affleck didn't stop for interviews, ET was on the red carpet and managed to ask the Batman v Superman: Dawn of Justice star about the upcoming season of Project Greenlight, which Affleck said he was "very excited" for.

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Project Greenlight returns to HBO in September for its fourth season after a decade-long hiatus. The series, which follows first-time directors who are given a chance to direct a feature under the mentorship of veteran filmmakers, is produced by Affleck and Damon, his longtime friend and collaborator, and Adaptive Studios.

Damon shared with ET why Project Greenlight is so important to both him and Affleck.

"For us, in particular, when we came on the scene with Good Will Hunting all those years ago, we kind of did it in a non-traditional way, and so a lot of people asked us, 'How the hell did that happen?'" Damon said. "So it always felt like there was some other way to launch some careers and we always felt it was kind of incumbent on us to do that."

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Over the weekend, Affleck was in Atlanta, where his estranged wife has been filming her upcoming movie, Miracles from Heaven. Affleck, Garner and their children -- Violet, 9, Seraphina, 6, and Samuel, 3 -- were spotted together at a local mall on Saturday before returning home to Garner's rental house.

For more on Affleck's time in Atlanta with his family, check out the video below.

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