At the 10th annual TCM Classic film festival, everyone was having what she’s having…

The opening night gala of the festival celebrated the 30th anniversary of the beloved romantic comedy When Harry Met Sally, and the film’s director, Rob Reiner, and stars Billy Crystal and Meg Ryan were on-hand to mark the milestone. The evening included a screening of the film at the historic TCL Chinese Theatre and an after-party with a live band playing many of the standards from the film’s score, including leading the crowd in a mock New Year’s Eve toast complete with champagne, confetti, and a round of “Auld Lang Syne.”

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Before the screening, the trio reunited to reminisce about making the film and recognize the late writer Nora Ephron (as well as the late Bruno Kirby and Carrie Fisher). Following Reiner’s introduction by TCM host Ben Mankiewicz, the stars behind Harry and Sally were wheeled out on a couch resembling the one used for documentary-esque interviews about marriage throughout the film. And to top it off, Reiner sang the movie’s love theme, “It Had to Be You” a cappella to welcome them to the stage.

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The trio touched on some of the most beloved scenes, including how the ending changed (in the original version Harry and Sally weren’t going to end up together) and the four-way morning-after phone-call between Harry, Sally, Jess (Bruno Kirby), and Marie (Carrie Fisher), which required three separate sets with working phones so the actors could hear each other and pick up their cues (it took over 60 takes to get it right).

But there is no scene more iconic than the one in Katz’s Delicatessen where Sally proves to Harry just how likely it is he’s been with a woman who’s faked an orgasm by performing one herself in front of the entire restaurant. It’s well-trod Hollywood lore that Crystal came up with the zinger of a line “I’ll have what she’s having” and that the woman who utters it is director Rob Reiner’s mother — but it turns out that the scene itself and Ryan’s big O fake-out was entirely her idea.

“Meg was the one who said, ‘I’ll do it. I’ll actually do it,'” recounting Reiner. “The idea was we gotta have something that men don’t know about women because earlier where they’re in the plane together and Billy talked about after sex how a man feels and all that, and we were saying we need a counterpoint, and Meg said, ‘I’ll do it, I’ll just actually act it out. We don’t have to talk about it. I’ll do it.’ And I had the idea, ‘[It’ll be] in a restaurant!'”

The one problem was when Ryan offered to do it she forgot about the fact that it would be in front of around 100 extras, and at first, was a little timid on set. So much so that Reiner proceeded to sit down and demonstrate just how far he wanted her to go with the bit, before realizing he was sitting directly opposite his own mother.

“She does a little thing at the end, which I didn’t tell her to do, she has a full-on orgasm and then she goes right back and she takes a little bite of coleslaw,” added Reiner. Crystal joked that because it took so many takes to perfect the scene he ate 27 pastrami sandwiches that day. “For any Jew, that’s a lot of pastrami,” he quipped.

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Mankiewicz asked Ryan where the idea for this bit came from and why she’d volunteer to do something so outlandish onscreen. “The comedy of Sally is so behavioral. It’s not so much talking, it’s doing, so it was very logical. It wasn’t hard to do,” she explained. “We all sat in Rob’s office for hours and hours just talking about [the movie].”

Crystal added that they had “weeks of talking” before they even started the multiple weeks of rehearsal that preceded filming. “The script totally changed from what we had agreed to do,” he said. “It kept growing and growing and growing. You had the guy point of view, and then you had [writer] Nora [Ephron] and Meg, throwing everything in it together, and that’s why I think it’s such a powerful screenplay.”

The 10th annual TCM Classic Film Festival runs April 11-14 in Hollywood.

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