'The Notebook' turns 15! Guess which pop star almost starred in the cult classic?

It may be hard to believe, but it’s been 15 years since The Notebook hit theaters back in 2004. Crazy, right? It’s been a minute, but the romantic film that placed Ryan Gosling and Rachel McAdams as our favorite on-screen couple continues to make us swoon with its romantic drama and memorable one-liners (“Say I’m a bird!” remember?) Based off Nicholas Sparks’ 1996 novel of the same name, The Notebook is now a blockbuster one can watch over and over again – and it never gets old!

When we think of the Blade runner 2049 actor and the Mean Girls star, we can’t help thinking of the roles that made them a cult-favorite couple, but would it have been the same love story if say Britney Spears or Jessica Biel would have played the lead role of Allie Hamilton? Keep reading to find out some fun facts about one of our favorite love stories.

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Ryan took his preparation for playing Noah to the next level

The then 23-year-old actor took his role of Noah Calhoun pretty seriously. Two months ahead of filming the actor moved to Charleston, during which he practiced carpentry by making furniture and even worked with a local cabinet-maker. The dining room table Noah makes Allie was actually made by Ryan.

"We shot a scene where Rachel and I consummate our relationship on a table I made," he told People. "But I couldn't keep it. We used a special wood, and the deal was [the cabinet-maker] got the table. But he doesn't know what happened on it."

Wardrobe malfunction

The memorable scene in which Noah and Allie share a passionate kiss in the rain turned out to be not so good for Rachel’s shoes and wardrobe. “That dress was made for the film, but a lot of the stuff I wore was rented and was actually from the 1940s," she said to Life & Style.

"I think there's a scene in the movie where I'm running in bare feet, and it's only because [after] the first few takes I did, the shoes disintegrated off my feet," she added. Yikes!

Family ties

As it turns out, director, Nick Cassavetes didn’t have to look too far for his mother, Gena Rowlands, plays older Allie in the film. As a matter of fact, the photographs of mature Allie and Noah through the years are actually photos of Gena and her late husband, John Cassavetes with James Garner, who plays mature Noah’s face photoshopped in over John's face.

Britney Spears almost starred as Allie

That’s right! The Toxic singer, who was one of Ryan’s co-stars back when they were part of the Mickey Mouse Club, screen-tested with the now father-of-two. In an interview with ET, Ryan stated, "I hadn't seen her really since she was about 12—we were both 12—so she's grown up, but she was really good, actually. She did a really nice job. We were 12, I don't remember much from when I was 12, but yeah, no, she did an excellent job, actually. That was cool."

Jessica Biel on the one that got away

Before Rachel landed the main character, Justin Timberlake’s wife, Jessica Biel also auditioned and even sees the role as one that got away. "That's one that I wanted so badly. I was in the middle of shooting Texas Chainsaw Massacre, and I auditioned with Ryan Gosling in my trailer — covered in blood,” she told Elle.

“Nick Cassavetes put me through the wringer in an interesting, excitingly creative way. But there's a million that get away. We're gluttons for punishment. It's just rejection," she added.

The birds scene was almost not gonna happen

Remember the epic scene in which Noah and Allie have that iconic kiss in the rain? Well, ahead of that memorable moment was the scene in which the lovebirds were actually surrounded by birds while taking a boat ride.

On the dilemma, director Nick Cassavetes said, "They were like, 'You can't do the birds. There's just too much—you've got to take the birds out.' We said, 'How come?' And they said, 'It just doesn't work. We talked to every animal wrangler—you can't do it. The birds aren't trained. You've got to take it out.'"

However, Nick fought back and even raised birds on the set for when it came time to film the legendary scene.