Eternal Sunshine of the Spotless Mind—Michel Gondry’s instant classic of a sci-fi romance, written by Charlie Kaufman, which debuted 15 years ago—originally had a much darker ending. The Oscar-winning film follows ex-couple Joel and Clementine (Jim Carrey and Kate Winslet) as they undergo procedures to erase one another from their respective memories, with much of the story taking place in Joel’s subconscious. By the end of the film, they’re drawn together again anyway, willfully ignoring the fact that their relationship may very well crash and burn once more.

That’s not how Kaufman wrote it, though. “We don’t end up together in Charlie’s version. I walk away,” Carrey said in a recent phone interview. Gondry—who was sitting next to Carrey—added that the screenwriter also considered flipping the narrative, revealing at the end that the story has been taking place in Clementine’s head the whole time. But both ideas were ultimately scrapped—and Gondry’s relatively happy ending won out instead. (Kaufman’s rep didn’t respond when we asked to comment on this story.)

With its homespun sci-fi aesthetic, aided by Gondry’s nifty, lo-fi special effects and lived-in romanticism, Eternal Sunshine was a quietly mind-blowing film, the kind that spawned plenty of thin imitators. But it took a lot of tweaking for the film to arrive where it did—which also meant that several scenes featuring notable bit players were left on the cutting-room floor. A post-S.N.L., pre-30 Rock Tracy Morgan, for example, played Joel’s neighbor in a few flashbacks that did not make the finished film. “He’s a comedic genius,” said Gondry—“Genius!” Carrey emphasized. But “the reality is he was Tracy Morgan”—which made his presence a bit of a distraction. (Morgan’s rep says the comedian doesn’t remember if he acted in the film.)

At least Morgan is in good company: the film also could have featured Ellen Pompeo, who had a scrapped scene as Joel’s ex-girlfriend, Naomi. To this day, Carrey swears Gondry cast Pompeo because of her glancing resemblance to Renée Zellweger, with whom he had just broken up before filming Eternal Sunshine.

“I was pretty hurt,” Carrey said. “Michel likes to have real feelings in the scene and real chemistry, so he hired Ellen Pompeo, who’s a wonderful actress. But she reminded me completely of Renée. Her look was similar. And I said, Bastard! And it ends up that she’s not even in the movie.”

“I don’t think they look alike,” Gondry said, denying Carrey’s theory altogether.

“We actually had really good chemistry. It was odd,” Carrey continued. “It was almost too much. If it had been in the movie, it’s competing [with Clementine].”

At the time of filming, Carrey had already established himself as a comedian with real acting range, having starred in The Truman Show and Man on the Moon. Still, he may not initially have seemed like the right fit for self-loathing Joel Barrish, a character so quiet that Carrey had to be aggressively mic’d while speaking his lines. But Gondry—a huge Carrey fan who said he rewatches Liar, Liar every year—said he knew Carrey should play the part when he went to see him on the set of the comedy Bruce Almighty. When Carrey was in-between scenes, Gondry saw a different side of him: “It’s the exact feeling when you walk into a party and you feel everybody knows each other but you,” explained the French filmmaker. “I always saw Jim like that. Like he doesn’t belong.”

So Carrey signed on for the film, excited to try something new. Gondry had one concern, though; his debut film, Human Nature (also written by Kaufman), was about to hit theaters, and he was pretty sure it was going to be a box-office flop, which could very well scare away the big movie star he had just hooked. “Michel and I sat in this restaurant, and he made me sign a napkin saying when Human Nature came out and was a bomb, I wouldn’t let him go,” Carrey recalled with a laugh. Human Nature ultimately made under $1 million, but that didn’t deter Carrey or Winslet from Eternal Sunshine.

Gondry, for his part, remembered knowing Winslet was exactly right for the part of the kooky, bewigged Clementine because she was the only person unafraid to give notes on Kaufman’s script. “I was really surprised by her honesty,” Gondry said. “Then I believed her when she said it was a great project.”

Once on set, the actors had to learn how to do things the Gondry way. He hates the word “action,” for example—so Gondry would simply start filming certain scenes without warning. His reasoning? “You say ‘action,’ and everybody becomes a piece of wood,” said Gondry. “And when you say ‘cut,’ everything becomes fluid and alive. So the word ‘action’ became like my enemy.”

Occasionally, the director would give his cast notes to try and spice up certain scenes; in an early encounter between Clementine and Joel on a train, she winds up and punches him in the arm, which wasn’t in the script. “She gave me a pretty good wack!” Carrey said, before addressing Gondry: “I immediately knew it was you.”

The film endures in large part thanks to Gondry’s tendency to avoid C.G.I.—technology that could easily look outdated to modern eyes—in favor of fantastical practical effects. For scenes in which Clementine had to magically pop up in different rooms, Gondry had trick doors built into the set that Winslet could quickly run through. For a scene in which the couple climbs all the way back into Joel’s babyhood memory of being bathed in the sink, Carrey and Winslet had to sit in a giant tub for several hours; at one point, Winslet actually fainted. Gondry wanted to keep filming, which made Carrey furious. “People’s nerves get frayed,” Carrey recalled. “Michel was going, ‘Shoot, shoot!’ and she was going, ‘I’m nauseous.’ And I got angry because she was not feeling well. So yeah, Michel and I had words.” Carrey was so mad, said Gondry, that the director thought things might get violent, asking his star, “Are you going to punch me in the face?”

By their account, that wasn’t the last time Gondry and Carrey yelled at each other on the set. Ultimately, Gondry says, they learned to work through their clashing artistic sensibilities—not least because their arguments had a tendency to bleed into scenes. “One of the last times Jim yelled at me, I started to yell back and said ‘Jim, if you yell at me, I don’t like you anymore. And if I don’t like you, I can’t direct you,’” Gondry said. When asked how they celebrated wrapping Eternal Sunshine, Carrey had a quick deadpan answer: “Michel and I had a fistfight in the street.”

Fifteen years later, the two appear to have found their groove. They reunited in 2018 for the Showtime series Kidding, which will begin production on its second season this May. “We’re like brothers,” said Carrey. They act like it, too—on the phone, they ribbed each other constantly, frequently launching into tangents and running through the corridor of old memories. Carrey was lightning-quick to help the thoroughly French Gondry pronounce tricky English words like “exhilarating” or “obstacle.”

Perhaps it helps that after a difficult production, Eternal Sunshine would end up being a decisive hit with critics, who praised the film for its original script, its unshakeable aesthetic, and strong performances by Carrey, Winslet, and co-stars Tom Wilkinson, Kirsten Dunst, Mark Ruffalo, and Elijah Wood. The movie was nominated for two Oscars: best actress for Winslet and best original screenplay for Kaufman, Gondry, and Pierre Bismuth. But though Eternal Sunshine would end up winning in the screenplay category, it was not nominated for best picture—nor were Carrey and Gondry nominated for actor and director, respectively. Neither one seems to have hard feelings about this; when asked about the snub, Carrey pointed out several other classic films that were ignored by the Academy (including 2001: A Space Odyssey). Carrey also disparaged the business of campaigning for an Oscar, which has become an industry unto itself.

“There’s a lot of monkey business that goes on around awards,” he said with a laugh, calling the whole thing a “gigantic clusterfuck . . . if you don’t show up to a certain dinner, you screw your chances and all those things. I’ve never been real good at playing that game.”

Carrey, as it stands, has never been nominated for an Oscar—a surprising bit of trivia, given his filmography. But he takes that in stride: “The only time I’ve ever felt a twinge of something about an award or not getting nominated is whenever people tell me I should be,” the actor said. “Like, really? Should I be disgruntled? I had a wonderful time and I met a bunch of people . . . isn’t that enough?”

“The reward for the director is to do another film,” Gondry added. “When it’s the first day of shooting, you can’t believe it.”

The other reward, of course, is creating a film that becomes a cultural touchstone the way that Eternal Sunshine has. There have been attempts to recapture that magic, Gondry said, including a Broadway adaptation (“I don’t think it can happen,” Gondry said) and a potential follow-up: “Charlie, I think, had the concept for a sequel,” the director said; Carrey quickly added that they shouldn’t speak for the screenwriter. There was also a planned TV adaptation in 2016, which ultimately fell apart. Neither Gondry nor Carrey were involved, but they both give the idea their blessing.

Though they both remember the film fondly, it’s not one they watch frequently. Carrey hasn’t seen it since it was released, while Gondry had a surprising experience upon re-watching: “I think the last time I saw it, I didn’t understand anything in it,” he said. Then Gondry and Carrey both started laughing.

“Like ‘What the hell have I done?’” Carrey asked.

“Yeah,” Gondry replied. “We mess around with the time. Yes, honestly, it’s complicated. I’m surprised that people like it so much—because I think they do.”

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