The actor was clearly in the mood to celebrate his latest movie release and was pictured laughing, joking and smiling non-stop at the LA red carpet event, alongside fellow stars of the new romantic comedy Michael B. Jordan, Imogen Poots and Miles Teller.
The three guys - who play best mates on-screen - each ensured that they looked as dapper as possible in contrasting coloured suits.
While Michael went for a light grey with a red skinny tie, Miles opted for navy blue and Zac kept it simple and super smart in all-black.
The 26-year-old heartthrob was in noticeably good spirits after admitting last week that he is the happiest he's ever been.
Last year proved to be particularly tough for Zac, as he fractured his jaw and reportedly entered rehab.
But he is now in a better place and credits his That Awkward Moment co-stars as being a strong support system.
"I've never been this happy before," Zac told the Today show. "I'm extra grateful for these guys [his Awkward Moment] co-stars and to be here promoting this movie. Things are good."
We can certainly tell just how close he and his actor pals are from these cute red carpet snaps.
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