The Meg Ryan and Tom Hanks classic romantic comedy “You’ve Got Mail” hit theaters 25 years ago.

“You’ve Got Mail” is 25 years old.

The movie, which hit theaters in December 1998, follows the story of Kathleen Kelly (Meg Ryan) and Joe Fox (Tom Hanks), who start an online romance after meeting in an over-30s chatroom and keeping up an email correspondence after hitting it off. Little do they know, they are business competitors, as Kathleen owns a small bookstore, and Joe runs Fox Books, a chain of big bookstores which is opening up shop around the corner from Kathleen’s.

The behind-the-scenes secrets from the set of the film are just as big as the secret Joe keeps from Kathleen when he finds out who he is falling in love with, but decides not to tell her.

Here are some fun facts from the set of “You’ve Got Mail,” including how Julia Roberts almost landed the role of Kathleen.

‘All kind of destiny’

Julia Roberts revealed she was offered Meg Ryan’s part in “You’ve Got Mail.” (Photo by: Charles Sykes/Bravo via Getty Images)

During a recent appearance on Bravo’s late-night talk show, “Watch What Happens Live with Andy Cohen,” Roberts shared if there were any movies she regretted passing on, revealing everyone’s favorite romantic comedy could have looked a little different if she had agreed to star in it.

“Well, none that I have regrets about because I feel it’s all kind of destiny,” Roberts said. “But what have I passed on that went on to be great and wonderful, and I thought it maybe wouldn’t have been as great and wonderful with me? ‘You’ve Got Mail.’”

She went on to say missing out on certain roles is par for the course for an actress, explaining Ryan almost starred as Shelby in “Steel Magnolias,” a role which earned Roberts an Academy Award nomination. Ryan “was supposed to be in ‘Steel Magnolias,’ and she was still filming ‘When Harry Met Sally,’ and so I got that part.”

Roberts admitted she has “lucked into some good stuff,” as she also revealed “Cate Blanchett was supposed to be in ‘Closer,’ but she got pregnant,” leading her to take over.

Meg Ryan and the Books of Wonder

Meg Ryan played the owner of a bookstore in the film and worked in a real bookstore to prepare for the role. (Photo by Ronald Siemoneit/Sygma/Sygma via Getty Images)

In the movie, Ryan played the lovable owner of The Shop Around the Corner Bookstore, Kathleen Kelly. It seems the actress took her role very seriously, working in a bookstore with her co-star Heather Burns for a while to get a better understanding of their characters.

“She actually rehearsed, which you don’t often get a chance to do in film,” Burns told Vanity Fair in February 2015. “We worked at Books of Wonder in the children’s bookstore for a week. . . . We learned the register so we would look natural when we got in the store.”

Asking the two stars to get real-life experience in a bookstore was only one example of director Nora Ephron being meticulous when it came to getting every detail right.

Producer Dianne Dreyer told Vanity Fair that Ephron “cared about detail in a big, big way,” including what the bookstore and costumes looked like, and making sure there was enough time for rehearsal.

“Nora always insisted on rehearsal — it was just like a note-taking frenzy for everyone, myself included certainly for [writer] Delia [Ephron] and for Nora,” Dreyer explained.

“It’s always a struggle to get the studio to pay for it because you have to have access to your actors for that much longer. Nora had her producer build it into every budget because she had to see what jokes play.”

‘Shopgirl’ username

Producers had to convince the woman who owned the “Shopgirl” username to let them use it in the movie. (Warner Brothers)

The AOL emails sent by the main characters played a huge role in the movie’s plot. In fact, they played such a big role in the film, producers titled it “You’ve Got Mail,” after the website’s famous greeting.

Originally, however, the film was called, “You Have Mail,” since producers were trying to avoid legal trouble, but after learning AOL had failed to trademark their iconic phrase, they changed it to the title audiences all now know.

While they did not have to put up a fight for the film’s title, they did run into some trouble when it came to securing the username Ryan’s character uses when emailing Hank’s character.

Producers of the film had to ask the woman who owned the username to relinquish the screen name, “Shopgirl,” so they could use it in the movie. Ephron revealed, the owner of the username “actually worked at an autobody shop.”

Based on a play from the 1930s

The movie is based on a 1937 Hungarian play, called “Parfumerie.” (Getty Images)

While the movie integrated what was considered modern day technology at the time, it was based on a play originally written in the early 1900s.

The Hungarian play “Parfumerie” was written in 1937 and followed the lives of the employees of Hammerschmidt’s Parfumerie, a family-owned business in Budapest, whose lives are turned upside down by rumors and suspicion.

The play, which focuses on finding love in unexpected places, had been adapted on both the stage and screen a few times, before the Ephron sisters wrote their interpretation of it.

The story was re-told in the film “The Shop Around The Corner” in 1940, and then again in the 1949 movie, “In The Good Old Summertime,” which starred Judy Garland.

Prior to returning to the screen for a third time in “You’ve Got Mail,” it appeared onstage in the 1968 Broadway musical, “She Loves Me.”

Hanks and Ryan’s third movie together

“You’ve Got Mail” was the third on-screen partnership between Meg Ryan and Tom Hanks, the first being “Joe Versus the Volcano.” (Photo by Warner Brothers/Getty Images)

Prior to starring together in “You’ve Got Mail,” Hanks and Ryan had already starred in two movies together, “Joe Versus the Volcano” and “Sleepless in Seattle.”

While their first movie together did not do so well, their second partnership earned the two of them Golden Globe nominations, propelled both of them to mega stardom and cemented Ryan as a queen of romantic comedies.

In “Joe Versus the Volcano,” Hank’s character learns he has six months to live, and is convinced by a millionaire to jump into an erupting volcano. When attempting to live his final days to the fullest, he encounters Ryan’s character, and they fall in love.

Ryan plays a journalist in “Sleepless in Seattle,” who, after hearing the story of a single father looking for love in Seattle on the radio, makes it her mission to track him down for a story. Despite being engaged, she falls for him and writes him a letter to meet her at the top of the Empire State Building on Valentine’s Day.

“He’s just so easy. He listens; he roots for other people,” Ryan told “Sleepless in Seattle” producer Gary Foster in December 2018 about their on-screen partnership.

“[Hanks] doesn’t like there to be drama. I feel the same way. We’re just really there to have fun, this is supposed to be a creative experience and there’s no reason to get heavy.”