Billy Crystal Recalls the 'Fantastic Chemistry' He Shared with Meg Ryan on When Harry Met Sally, 35 Years Later (Exclusive) 

It was romantic comedy magic in the making.

In an exclusive interview with PEOPLE, Billy Crystal reflects on his now-classic romantic comedy When Harry Met Sally, directed by his longtime friend Rob Reiner from a script by the late Nora Ephron. He tells PEOPLE that he didn't know at the time that the movie would be so beloved 35 years after its release, but that he felt confident in the storm of talent that brought the movie to life. That storm includes what he calls his “fantastic” chemistry with costar Meg Ryan. 

“You knew it was special,” the 76-year-old actor tells PEOPLE of working on the movie. “You don't know that it's 35 years special.”

“You know that it was a terrific script. Meg and I had a fantastic chemistry together,” he explains. He also praises the late Carrie Fisher and Bruno Kirby, who played the movie’s secondary couple, Marie and Jess, as “great.”

“All you can control is the experience,” the Monsters Inc. star explains. “And it was a great script, phenomenal director, great director of photography, Barry Sonnenfeld, who later became a terrific director himself. It came at a perfect time for us in our lives, and it just felt good. But you don't know what's good until you see it all put together.”

Crystal explains that he finally got to see it all together at the first test screening in Pasadena. “I was sitting in the back with Rob and the movie's playing amazingly well,” he remembers. “And then the deli scene came on and the audience laughed like you can't believe,” he recalls, referencing the now-iconic line “I'll have what she's having,” which was delivered by Reiner’s mom Estelle.

“Rob had to add footage on the other side of [the line] because the laugh was so big,” Crystal says. 

The actor is thrilled that “all these years later” there’s still “so much affection” for the film and its title couple. Not only is the movie “so revered,” he says, but “new generations, they love it too.” He says, “It's not like, ‘Oh, it's my parents' movie.’ This still is for everybody. That's really good.”

He also says When Harry Met Sally is still the movie he’s recognized most for, though Monsters Inc., in which he played Mike Wazowski, also has vocal fans. “It's fortunate, I've been in movies that there are some moments that stick with people,” he says. “I'm glad that the movies have meant something.”

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Crystal’s Harry is a divorced lawyer with a cynical side that was based in part on Reiner, now 77, while Ryan’s Sally was based in part on Ephron. And both Crystal and Ryan, 62, became autumn style icons, with the You’ve Got Mail star inspiring Meg Ryan Fall, and Harry’s wardrobe beloved for one particularly iconic sweater.

But Crystal tells PEOPLE he doesn’t know where that cozy, white sweater is now. “I made a donation,” he says. “I believe it was to UCLA’s theater department with tons of clothes for costumes. I have a feeling it’s there.”

The City Slickers star’s newest project is the Apple TV+ series Before, which he stars in and produces. The streamer describes the show as an “atmospheric, character-driven psychological thriller.”

You can watch Before every Friday on AppleTV+. It runs until Dec. 20.