In 2017, Daddario was rumored to be dating Zac Efron, 33, after the two played each other's love interest in Baywatch. While she and Efron never officially confirmed their relationship, People reported in May 2018 that they had been seeing each other "on and off" since co-starring in the movie.
Fans had been speculating for a while that the actors had taken their romance off the beach and into real life, which prompted Daddario to deny the rumors in May 2017.
"We work together closely; he's my love interest in the film. I understand why people would go crazy over something like that, but Zac and I are very good friends," she told E! at the time.
However, despite her being adamant that the two weren't together, their social media posts painted a different picture.
In 2018, "Efron was noticeably present on Daddario's birthday Instagram post, watching her blow out her cake candles," writes Elle.
The Greatest Showman actor later posted a sweet tribute to Daddario, sharing a photo of them snuggling together and "looking totally like a couple."
"Happy birthday to one of the the [sic] most real, down to 🌎, stunning, intelligent, creative, loving, and most rare Pokémon ever created #alexdaddario," he captioned the pic. Check it out below!