For years, Shrek was considered the ugly stepchild of the DreamWorks empire. 

The way director Andrew Adamson saw it, company co-founder Jeffrey Katzenberg "was going through his 'I want to make serious animation for adults,'" Adamson recently told Inverse. And the flatulent, anti-social, cantankerous AF ogre didn't exactly fit the bill.

"This was sort of a bastard child," Adamson continued. "It was the island of misfit toys to a large degree. Everyone who didn't work out on another project got sent onto Shrek."

Agreed editor Sim Evan-Jones, "There was always a little bit of a rebel spirit about the Shrek gang. There was a shared empathy that everyone wanted to do things in an unconventional way."

So they kept plugging away, writing their crude jokes and perfecting their computer-generated animation. And when Katzenberg saw the finished project—in which a repugnant ogre joins a wise-cracking donkey on a quest to save a princess in a send-up of every animated movie that came before it—he was a believer. 

"We had one screening where we'd scored something really high," Adamson recalled. "And I remember Jeffrey saying to me afterward, 'Get ready for this. This may only happen once in your life.'"

This turned out to be a $3.5 billion-grossing franchise, the all-star cast of Mike Myers (the titular ogre), Cameron Diaz (Princess Fiona) and Eddie Murphy (Donkey)—and 95 minutes of literal LOL-worthy jokes, largely at Disney's expense, leading to a $484.4 million box office gross, an Oscar, two holiday specials, a spin-off, a Broadway show and four sequels with Shrek 5 set for a July 2026 release. (Not to mention all the merchandise that has flooded the market since the original film premiered on May 18, 2001.) 

Plus there's that earworm of a cover song from Smash Mouth. 

So the ending was certainly happy, but Shrek's origin story—dating back to Steven Spielberg purchasing the rights to the book of the same name in 1991—wasn't exactly the stuff of fairytales.

To properly recognize a movie the Library of Congress deemed worthy of preservation in the National Film Registry, we must start at the beginning. 

Once upon a time, there was a picture book, a legendary director, a former Disney CEO and their brand new animation studio...

1. It all started with a book. And we don't mean the collection of fairytales the titular ogre was pawing through on the toilet in the opening scene of Shrek. William Steig's 1990 children's book Shrek! flipped the traditional girl-meets-her-prince-charming-and-they-live-happily-ever-after narrative on its head and it was beloved by producer John Williams' kids. 

"They loved it and showed it to him," eventual star Mike Myers told Cinema.com of the film's origin. "Then he brought it to Jeffrey Katzenberg at DreamWorks, and he got DreamWorks interested in it. So they ended up turning this little 28-page book into the movie. And it's all about this stinky, smelly ogre who doesn't care what anybody thinks of him."

2. Originally cast as the voice of Shrek, Chris Farley had nearly recorded all of the dialogue before he died of a drug overdose in 1997. After his passing, "We kind of lost our way for a considerable amount of time," director Andrew Adamson admitted to Inverse. "It was devastating on a personal level. I actually said to Jeffrey, 'Can you please fire me? I can't bring myself to quit.' But he didn't. And then Mike came on and then we refocused and recentered."

3. For Myers, it was an easy yes to sign on. "When they told me about the movie and said that Eddie Murphy, Cameron Diaz and John Lithgow were in it, I told them right away, I'm in," Myers told the site. "And I loved the whole idea behind the story, which is that you're beautiful, so don't let other people tell you that you're not just because you don't look like the people in magazines. Or because you're not that weird ideal body image that's out there right now."

4. One thing producers didn't tell him: That he wasn't the first choice. "I guessed it right. They weren't going to tell me," he revealed on a 2014 episode of Marc Maron's WTF podcast. "I was working on [the movie] and I looked at the maquette of Shrek, you know, the little clay model that they make, and I said, 'Was this offered to Farley? It looks like Chris Farley.'"

5. After he took the part, Myers told Cinema.com "they changed some of their ideas about the character. Like giving me a Scottish accent." Really, he landed on the thick brogue after first trying out the voice from his Saturday Night Live "Lothar of the Hill People" sketch and an amplified version of his Canadian accent. 

"I thought, well, Scottish people are fantastic at being super-happy and then getting super-mad," he explained on the WTF podcast, "and I thought, that's an ogre!" (A reported $4 million expense, it turned out to be money well spent. Myers framed a letter from producer Steven Spielberg thanking him for taking the time to redo it.)  

6. Another major switch involved leaning fully into computer animation. Because they originally intended the film to be motion-captured.

"What they wanted to do was use puppets for the four-legged characters," editor Sim Evan-Jones told Inverse. "They had people in fat suits. And it was just a big fat mess. It was a Shrek character that was not the same but not dissimilar to the one we ended up seeing in the movie: guy in a fat suit walking through an alley in a town and then he's mugged by this character they called the Mugger. Shrek was accompanied by the donkey, who was played by a person using their feet for the back legs and brooms for the front legs." 

7. Oh, right, the original story was also grim AF. Set in the Middle Ages, "The story was too dark…and driving the look of the film too dark as well," production designer Guillaume Aretos told Vice in 2016. "It could've been an obscure cult movie if it had been done like that. Jeffrey didn't want that, he wanted a story that would be original—and at the same time pop."

As they began the redesign, they got to the scene where Shrek and Donkey go to visit Lord Farquaad about getting the storybook castoffs removed from Shrek's swamp.

Farquaad "wants his population to be happy by force if necessary—and everything is neat and perfect," noted Aretos. "So we started designing and the images that came out…looked like Disneyland. Jeffrey Katzenberg looked at the images we made and said, 'That's exactly Disneyland. Go for it, that's even more fun, push it.'"

8. Nicolas Cage was offered a chance to play the ultimately lovable ogre, but has no regrets about passing on the billion-dollar franchise. "Well, the news said it was because of vanity. I think that's a bit strong. But the truth is, I'm not afraid to be ugly in a movie," he explained on Today in 2013. "When you're drawn, in a way it says more about how children are going to see you than anything else, and I so care about that."

He turned down the part for the same reason he decided to voice Grug in that year's Croods. "I want kids to look at Grug [and think] 'Well, he's a little scary, but he's a big teddy bear,'" Cage noted. "And I wasn't sure I could do that with Shrek."

9. Diaz also wasn't the initial choice to don Fiona's crown, with Janeane Garofalo originally cast. "I was never told why," Garofalo told Vulture of losing the part. "I assume because I sound like a man sometimes? I don't know why. Nobody told me."

10. And John Lithgow had to make quite the concession in accepting the role of the pint-sized monarch with a Napoleon complex. "I always said I would never play anyone short," the 6-foot-4 star admitted to the Los Angeles Times in 2009, "and then came Lord Farquaad. There's always something new that I hadn't thought of. I'm usually the subject of someone's brainstorm. I get very surprised by the things people offer me, and I just get excited about the next thing I do."

11. One of the funniest bit was inspired by a children's record. Tasked with figuring out a scene with the Gingerbread Man, "I went back to my desk and sat down," storyboard artist Conrad Vernon told Inverse. "I was like, 'What do I know about the Gingerbread Man?' And I had this little TV set with a record player on top of it. And on one side of the record was the 'Gingerbread Man' and on the other side of the record was 'Do You Know the Muffin Man?'"

That sparked his brilliant idea: "What if they were torturing the Gingerbread Man for the information? How do you torture a gingerbread man? Well, you break his legs off, you dunk him in milk," Vernon continued. "I was like, 'Maybe he doesn't sing the 'Muffin Man' song; maybe it's like an interrogation.' I wrote it out on a piece of paper and then boarded it out. And when I pitched it, I used that voice."

Katzenberg was impressed with his humor and his voiceover skills. "They tried for about two months to find actors to replace me," Vernon said of eventually playing the character in the film, "but they finally just said, 'Screw it. We can't find anyone. Can you do it?'"

12. Gross out humor was also heavily encouraged. "The opening scene, where Shrek is reading the fairytale book and then it's revealed that he's in the toilet," recalled storyboard artist Chris Miller, "that got a laugh at a screening, and then suddenly it was free rein to make it a full-on comedy."

And so they did, director Adamson telling Inverse, "We really did make the movie for ourselves, and made it accessible for children rather than making a movie for children that was accessible to adults."

13. During the process, they got down and dirty. Some of the film's developers took actual mud showers as research for Shrek's preferred bathing method. And art director Douglas Rogers found himself fending off an alligator during a trip to a magnolia plantation he booked to gain inspiration for Shrek's swamp. 

14. Shrek is more or less responsible for every DreamWorks picture that followed. Think: Madagascar, Kung Fu Panda, Monsters Vs. Aliens and How to Train Your Dragon.

"They defined us as a company in terms of what a DreamWorks Animated movie is and can be and should be, so they really helped us find ourselves," Katzenberg said of the franchise in a 2007 interview with The Age. "That first Shrek saved the company financially. We're here today because of it. It's been a great blessing. I refer to it as the gift that keeps on giving."

(E! and DreamWorks Animation are both part of the NBCUniversal family.)

(Originally published May 18, 2021 at 3 a.m. PT)