Not only were their fans delighted to see them pictured alongside one another, which doesn't happen very often at all, but they were also left totally swooning over the X-Men star.
Michael looked effortlessly dapper in a black tux and bowtie combo, while Alicia wowed in a floor-length gown. The dazzling dress was a nude shade and adorned in diamantes, creating the most eye-catching look.
After outlets shared photos of the couple together, the fan comments came flooding in, many of them commending Michael on his ageless looks. "Fassbender is still breathtaking," penned one, with another added: "Oh Fassbender," with a starry-eyed emoji. A third added: "He is so handsome."
Alicia and Michael hugged and even kissed for the cameras. See the best photos during their red-carpet appearance…
The intensely private couple, who married in 2017, have a baby together, but this was only revealed after the little one arrived.
The two fell in love while playing husband and wife in The Light Between Oceans in 2014.
Although the Lara Croft star is usually notoriously private about her relationship with Michael, when Kate Garraway asked her about the actor during an interview on Lorraine, Alicia said: "Well, I've had the most happy year... It's a lovely thing to choose to be private, even though you've got this career."
Where do Alicia Vikander and Michael Fassbender live?
Swedish born Alicia and her Irish husband Michael have laid down roots in Lisbon, Portugal.
The decision came after Michael had mentioned he always loved the Portuguese city and that they had friends who lived in Europe. "When I met my husband three and a half years ago, he had mentioned he’d been to Lisbon and loved it, and I knew friends who were moving out there. And that was a time when I was just starting to feel really at home in London. But after Brexit I think I was like, 'Meh, you know what, I want to stay in Europe,'" she told Elle.
Cannes has been full of fashion forward looks as always and here are some of our faves: