Going into the 65th Oscars, held thirty years ago today, the sentiment was one of finally crowning royalty – neither Clint Eastwood (the director of Unforgiven) and Al Pacino (a double acting nominee for Glengarry Glen Ross and Scent of a Woman) had ever won. In fact, Eastwood had never even been nominated! (Both did indeed win; Pacino took home Lead Actor for Scent of a Woman.)

But the talk of the industry ended up being a different story altogether the next day. Marisa Tomei was an upset win in the Best Supporting Actress category for My Cousin Vinny, a comedy released nearly a full year earlier. And I’ll say it: this is the last time an actor ever won for a movie they took on with no expectation it would augur an Academy Award. This is perhaps the greatest upset in Oscar history.

Vinny was a hit upon its spring 1992 release, although it ended up being more of a breakout vehicle for Tomei, thanks to her screen partner, Joe Pesci, on a roll after his own Goodfellas Oscar win and in between two massive Home Alone hits, than a comeback vehicle for co-star Ralph Macchio, as it was initially promoted. But it had largely fallen out of the Oscar conversation – which wasn’t as loud of a conversation in the pre-Internet, pre-social media days of trade ads, cover stories and Barbara Walters interviews.

But 20th Century Fox did indeed mount a “For Your Consideration” campaign for Tomei, who had not received a Golden Globe nomination but had won a Most Promising Newcomer award from the Chicago Critics’ Association. (Had the Critics’ Choice or Screen Actors Guild Awards existed back then, they might have shown the Academy’s hand a bit more). And she was the fifth and final nominee announced in a category that also included Judy Davis (Husbands and Wives), Joan Plowright (Enchanted April), Vanessa Redgrave (Howards End) and Miranda Richardson (Damage). That she had also starred in the Oscar-baity Chaplin and was also doing press for the Christian Slater romantic drama Untamed Heart during awards season likely helped, too. (In my own personal category, I’d swap out Plowright and Redgrave for Bonham-Carter in Howards End and Michelle Pfeiffer as Catwoman in Batman Returns, which is a leading role, but she’d already mounted a successful campaign in that category for Love Field the same year.)

Davis was the presumptive winner, though I had thought Plowright, On Oscar night, presenter Jack Palance stunned everyone when he read Tomei’s name. I was caught up in a joke he made right before he opened the envelope, erroneously claiming that all five nominees were foreign – four British, and Tomei, from Brooklyn. (Hardee har har.) You can see the Australian Davis reacting to this mis-labeling just as Palance opens the envelope; in fact, and in real time, the whole experience feels so unexpected, so implausible, so it-can’t-happen, it’s almost surreal.

Tomei acquitted herself with a nice impromptu speech, and theories as to how she could have prevailed began immediately. Could it indeed have had something to do with the Palance joke, with voters picking a local girl? (Five years later, Helen Hunt, too, was the lone American nominee, and she won Best Actress for As Good As It Gets.) Or could it have been because she starred in the only comedy nominated in the category? (A fate that Hunt also enjoyed, too.) You can see the reaction of joyful surprise on the face of Mary McDonnell, a nominee seated near Tomei at the Dorothy Chandler Pavilion.

Negative talk abounded, too, suggesting an overall snobbery – about age, about experience, about class (both about Tomei, a relative newbie to fame, and her thick-accented character, Mona Lisa Vito), about genre film work. Many postured a theory that an older, addled Palance had erred, and merely just read the final name outside the envelope. That is unlikely; Academy spokespeople always assured that in the event of the wrong name being read aloud, a member of the accounting firm would point it out and someone from the Academy would correct it onstage – a scenario that we did see play out 24 years later during the infamous La La Land/Moonlight Best Picture debacle, leading to the hashtag #mycousinvindicated.

Here’s the thing: Tomei is great in the movie: pure joy and instantly iconic. (I still say the “My biological clock is tickin’ like this!” scene should have been her Oscar clip). Mona Lisa is a heroic part that showed off the actress’s comedic chops. She and Pesci share a terrific chemistry; they’re a ‘90s version of Nick and Nora Charles, courtesy of the Verrazano Bridge. And it must have connected with voters. When it comes to awards and an outlier gets in as a surprise nominee, chances are that means they have enough support to take it all the way. (See Ewan McGregor at the Emmys for the otherwise-ignored Halston, and recent Tony victors Andrew Burnap and Deidre O’Connell.) Tomei had connected to Academy voters, and they liked her. (Some might say they liked her, they really liked her.)

The Oscar upset did follow Tomei, and if she couldn’t quite shake it, she made the most of it, even lampooning it on Saturday Night Live when she hosted during the release of her film, Only You. That film fizzled, and few true leading roles came her way. If her Oscar win wasn’t quite a “star is born” moment, Tomei was certainly able to channel the goodwill fans in and out of the industry had for her into  a rich resume that included frequent television work, Broadway performances, membership in the Marvel Cinematic Universe, and two subsequent nominations for Best Supporting Actress, for 2001’s In the Bedroom and 2008’s The Wrestler. Three decades since her Oscar night victory, Tomei has proven to have real staying power – her strengths are really as a powerful character actress. Either way, her (legitimate) Oscar win was not only the start of a successful long-term career, but a rare unpredictable Oscar night win that people still remember.