And so the lion reunited with the lamb. 

Catherine Hardwicke, the director of the first Twilight film, recently revealed that she crashed Robert Pattinson's 37th birthday back in May—and that she wasn't the only one. Edward Cullen's celebration was also attended (or crashed) by none other than Bella Swan herself and Robert's IRL ex-girlfriend, Kristen Stewart.

"Strangely enough I went to Rob's birthday party recently," Catherine told Josh Horowitz during a special Nov. 20 episode of his Happy, Sad, Confused podcast. "I kind of crashed with my friend Toni Collette. And then Kristen crashed it too!"

She added, "So that was just a few months ago, it was just like, 'Oh my god.' We all hugged each other, like, 'This is so crazy and cool.' I see them both at parties, events and everything, they're both lovely."

Catherine also reminisced on the massive opening of the 2008 film and how Robert and Kristen's lives, much like those of Edward and Bella, were irrevocably changed. 

Specifically, the director recalled an event they went to for the Rome Film Festival, where what was supposed to be a small signing at a bookstore turned into an event with fans lined up for blocks. And since they'd shown up with no security, expecting a small event, the three then had to push through the massive crowd to get to their car to leave at the close of the signing. 

"We finally get into the van," Catherine told Josh, "pull each other in, and we try to drive, we couldn't even drive and suddenly went, 'Okay this is not just a little movie. These people are going nuts.' After that we had to have security, everything. That's when we knew, 'Okay, this is big.'" 

And indeed, Stephanie Meyer's book-to-movie adaptation would go on to become hugely popular—its five films earning over $3 billion at the box office in total.

For more secrets about the beloved, blood-chilling franchise, keep reading. 

1. When first writing Twilight, screenwriter Mark Lord recalled fears that the male audience wouldn't be interested. "They wanted to take the concept [of Romeo and Juliet with vampires] and build in a structure that was far more a cinematic structure," he shared on The Big Hit Show podcast in January 2022. "And they wanted to just put in more action to advance it more and give something more for the male audience. They thought they were going to lose the male audience with too much of a romance."

2. Director Catherine Hardwicke quickly made the writers pivot after throwing the first draft into the trash. "The original script literally had Bella on jet skis being chased by the FBI," she recalled. "She was a star athlete. Nothing to do with the book."

3. Paramount and MTV initially had acquired the film rights to Twilight, with the original script making significant changes to the book. "It had veered very far from the book, and so I did not like it at all," director Catherine Hardwicke revealed to CinemaBlend. After three years, Paramount released the rights and then-independent film studio Summit Entertainment, immediately picked them up.

4. Book author Stephenie Meyer had some strict guidelines when it came to the adaptation of her source material. She didn't want any stereotypical vampire elements added in and demanded that Edward's "so the lion fell in love with the lamb" line make it into the final version. She also stepped in to have Kellan Lutz take over the role of Emmett when she didn't agree with the initial casting choice and asked to have Bella and Edward's first kiss toned down. Of stepping in to put her foot down, Meyer told EW, "That's hard for me, but I'm glad of every time I did it and I don't think I stepped on too many toes and everyone seems to still like me."

5. According to Summit's then-Head of Production Erik Feig, Meyer was adamant that her vampires didn't have fangs. "The negotiated language says, 'No actor playing a vampire will have canine incisors longer than those found in the average human being,'" he recalled on Spotify's The Big Hit Show podcast. "And that to me is... I love that line." 

6. Some soon-to-be-major actresses (including some who would become faces of their own respective franchises) that auditioned for Bella Swan included Emily Browning (Meyer's early first choice), Michelle Trachtenberg, Lily Collins and Jennifer Lawrence. 

"I didn't really know what it was," Lawrence later said on The Howard Stern Show of her Twilight audition. "You just get like five pages [at the audition] and they're like, 'Act monkey.' And when it came out I was like, 'Hot damn. Whoa!'"

7. Based on a suggestion from Emile Hirsch, who starred opposite Kristen Stewart in Into the Wild and was in Twilight director Catherine Hardwicke's Lords of Dogtown, the filmmaker zeroed in on Stewart for the role.

"I see Kristen…with all that longing and just lusting for Emile [Hirsch] And I'm like, 'Oh my God, that is so what I felt from the book. This girl that has so much longing, and it's so contained, and just repressed longing, but it was so palpable,'" Hardwicke said of watching Stewart in Into the Wild. "So I thought, 'Oh, it's got to be Kristen.'" 

8. While the actress initially had no interest in the project upon hearing the synopsis, but after meeting with Hardwicke and going through the script together, Stewart quickly changed her mind. 

9. Over 5,000 actors reportedly went out for the role of Edward Cullen, including Dave Franco, Jamie Campbell Bower (who would go on to play Caius in the follow-up films), Schitt's Creek's Dustin Milligan and Michael Welch (who landed the role of human Michael Newton). Moreover, Henry Cavill was Meyer's first choice, but was too old by the time the movie came along. He was reportedly considered for the role of Carlisle, the Cullen family patriarch.

But the final four contenders were Robert Pattinson, Ben Barnes, Shiloh Fernandez and Jackson Rathbone (who would eventually nab the role of Jasper Cullen), and they were all brought to Hardwicke's home in California to test opposite Stewart.

10. The chemistry read involved the infamous meadow scene, which Stewart and Pattinson performed on Hardwicke's bed. When it came to the kiss, Hardwicke recalled Pattinson being a bit too revved-up, but told EW, "It was electric." Pattinson later revealed he took half a Valium before the make-or-break audition. 

After the four actors tested, Hardwicke was still uncertain, but Stewart knew who her Edward was right away, telling Vanity Fair, "I was like, "'Are you kidding me!? It's such an obvious choice!'"

11. Prior to landing Twilight, Pattinson had considered leaving the entertainment industry after a string of failed auditions following Harry Potter and the Goblet of Fire (RIP Cedric Diggory!). "I was going to quit [acting] because I never got any jobs," he would recall on Today, "so I guess it's not really quitting when you're not getting jobs—it's just surrendering to fate."

12. While he would go on to play the titular teen wolf in MTV's hit series Teen Wolf, Tyler Posey revealed he auditioned against his good friend Taylor Lautner for the role of Jacob Black in the first film. "So, yeah, I auditioned for Twilight, Jacob Black. Taylor Lautner beat me," he told MTV with a laugh. "Congratulations, dude. That's a sick role. That's awesome. I hate you."

13. Another young star who auditioned for a role in Twilight was future Pretty Little Liars actress Lucy Hale who wanted to play Alice Cullen (she would also audition for Jane in New Moon and Leah Clearwater in Eclipse). She told J-14, "I read the books and I wanted to be part of the first movie so bad."

14. After initially going out for the role of villain James, Cam Gigandet (known for his bad boy turn on The O.C.) was brought back in to read for Emmett Cullen. "So I was like, 'Is there anything you guys have for me? Anything at all?' And so I went in for Kellan Lutz's character," he told MTV. "Once I went in, I was like, 'Oh my gosh, I like this character, but I just have to play James.' We waited a little bit, and after about a week, we heard back, and they were like, 'OK, we'll give him the job.'"

15. Meyer made a brief cameo in the first film as one of the diners in a scene between Bella and her dad Charlie (Billy Burke). She would also appear in Breaking Dawn: Part 1 as a guest as Bella and Edward's wedding, along with screenwriter Melissa Rosenberg, co-producer Bill Bannerman and producer Wyck Godfrey. 

16. "On the first shot on the first day I strained one of my ass cheeks, my ass just couldn't take the strain of the first one," Pattinson revealed to Jimmy Kimmel . His injury caused a problem with the company insuring the film and led to a bit of physical therapy for the star.

17. When New Moon was officially announced the day after Twilight dominated its opening night at the box office, fans were shocked to see Lautner not listed among the cast members. But it wasn't a typo, as the studio confirmed it was assessing whether or not the 16-year-old could play the character after his wolf transformation. 

"The doubts came up because he had very few scenes in the first movie, and also because he's described as being 6-foot-5 in the second book, so there were reasonable facts that we had to come to grips with," New Moon director Chris Weitz explained to Reuters of the 5-foot-9 star.

18. In fact, there was even an actor in mind to take over the part: The Scorpion King 2 and One Tree Hill star Michael Copon. "I have nothing against Taylor personally. I think he's great and tremendous at what he does," Copon told MTV. "But it's just adjusting to the fact that Jacob has to grow. It's a matter of going with the storyline."

19. But Lautner was committed to playing Jacob, taking on an intense training regime to bulk up as soon as production wrapped on the first film. His prep included consuming 4,000 calories per day, eating every two hours and working out for two hours at least five days a week.

"I knew I had to get to work right away; there could be no waiting involved," the then-17-year-old told Interview. "The day I finished Twilight, I came home and started bulking up. For New Moon, I'm 30 pounds heavier than I was in Twilight."

20. While Lautner (and his legions of fans) enjoyed his physical transformation, there was one aspect to playing Jacob that the actor was didn't like: that wig. "There was hatred between both of us," he told MTV. "It did not like me, I did not like it. Not fond memories."

21. After dying her hair blonde to play Cullen family member Rosalie in the first film, Nikki Reed opted to wear a wig for the rest of the series to protect her hair. "My hair fell out," she revealed to MTV of the damage. "It took 36 hours initially to make me blond, and every other day, I was bleaching my head and my skin. This time around, we are testing out different wigs and stuff."

22. More wig woes: After cutting her hair to play Joan Jett in The Runaways, Stewart had to wear a wig for Eclipse, one that earned a lot of eyebrow-raises. Leading up to Breaking Dawn: Part 1, Stewart assured fans she would be rocking her own hair and revealed Summit really didn't want her to chop her hair in the first place. 

"They're going to hate me for this, but they offered me lots of ridiculous... many ridiculous things to not do that," she told George Lopez in 2010. "I completely understand, I just thought we'd have a better...wig, and, uh, it's OK, we worked it out, and hopefully, hopefully, hopefully, it's OK now."

23. After originating the role of villain vamp Victoria, Rachelle Levefre was replaced by Bryce Dallas Howard (who was first approached to take on the role years prior) in Eclipse. And Levefre was not happy about the casting change, which the studio attributed to scheduling conflicts. 

"I was stunned by Summit's decision to recast the role," Levefre said in a statement. "I was fully committed to the Twilight saga, and to the portrayal of Victoria."

24. Newcomer Xavier Samuel won the role of Riley, Victoria's sidekick, in the franchise's third installment, reportedly beating out Channing Tatum and Harry Potter star Tom Felton for the job.

25. Michael Sheen took on the role of Volturi coven leader Aro because his daughter Lily (with Kate Beckinsale) was a massive fan of the series. "I was mainly excited about it because I knew I would make my daughter very happy," he told The Daily Record. "That was the main reason, and then I read the books and I really enjoyed them. I didn't think I was going to, but I really did."

26. For Bella's highly anticipated wedding dress, production turned to Carolina Herrera. "Carolina had worked with Stephenie personally for events. And they'd struck up a friendship and dialogue so we talked to Carolina for the dress," costume designer Michael Wilkinson revealed to MTV. "They'd been talking about the day that this dress would hit the big screen for a while and I was happy to help with the design as a consultant because it had to work with the rest of the film." For the rest of the Cullen women and Bella's mom, the costume designer created original dresses for each character. 

27. The problem with a custom couture wedding gown? The chances were high of it getting ruined—which almost happened due to the bad weather in Oregon—and they only had two duplicates. "I had a vision of the wet paint slowly creeping up the hem of the dress, but in the end, we got away with it," Wilkinson told InStyle. "We shot the wide shot first, and sure enough, by the time we moved in for the close-ups, the hem was soaking up the paint like a thirsty sponge!"

28. Okay, but how did Edward get Bella pregnant when he's, you know, dead, and she's not? Meyer actually provided an answer to this question on her official website back in the day: "Like with vampire skin—which looks similar to human skin and has the same basic function—fluids closely related to seminal fluids still exist in male vampires, which carry genetic information and are capable of bonding with a human ovum." So there you go. 

29. The original cut of Bella and Edward's wedding night sex scene initially caused Breaking Dawn: Part 1 to receive an R-rating, with director Bill Condor forced to tone down the couple's highly awaited first time. "There are very specific guidelines on thrusting intercourse," he told The Hollywood Reporter.

30. Pattinson nearly caused the fanbase to combust in 2011 when he revealed at a press conference for Breaking Dawn that a real priest was used for the wedding scene, "So technically we are already married because he did all the things you would do in a normal ceremony," he explained. "So we don't have a civil union in law, but I guess in the church we are actually married."

31. After Stewart wore a B.B. Dakota coat in the first film, the clothing company rebranded it as "the Bella Swan jacket." Summit swiftly filed a legal claim and in 2011, a judge ruled in their favor.

32. Stars you may have forgotten appeared in the franchise's films include Anna Kendrick, Shameless' Noel Fisher, Lost star Maggie Grace, Lee Pace, Westworld's Angela Sarafyan and Oscar winner Rami Malek. In fact, Kendrick kind of forgot she was in the series. "Holy s--t," she tweeted in 2018. "I just remembered I was in Twilight."

33. In an interview with Vulture years later, Hardwicke didn't exactly have fond memories of her time reading the scripts for Twilight, admitting, "Every one of those scripts sucked. Oh Lord, did they suck." She isn't the only franchise director to bash the series, with David Slade having to apologize for disparaging comments he made before signing on to direct Eclipse. "Twilight drunk? No, not even drunk. Twilight on acid? No, not even on acid? Twilight at gun point? Just shoot me,'" he once said during a radio interview.

34. A 10 year-old Mackenzie Foy landed the integral role of Renesmee, Bella and Edward's half-vampire half-human baby that Jacob imprints on (LOL remember that?). And the entire production team and cast were protective of the newcomer on Breaking Dawn: Part 2. To protect the newcomer, director Condor placed a swear jar on set (it accumulated more than $800!) and the two leads went just a bit meta. 

"They were amazing with her," Condor told EW. "It really brought something paternal out in Rob, and Kristen was especially protective. I'd have to interrupt them when they were in deep conversation to get going with a scene."

While CGI was ultimately used to portray the baby version of Renesmee, it was later revealed the production team attempted to use a doll to extremely creepy results. Seriously, it earned the nickname "Chuckesmee."