15 details you probably missed in 'To All the Boys 2'

In the first movie, John Ambrose briefly appears holding Lara Jean's letter. He was played by actor Jordan Burtchett.

In the sequel, John Ambrose is played by Fisher instead.

Netflix has not directly addressed why this role was recast, but has said many actors auditioned to play John Ambrose in the second movie.

During the sequel, Lara Jean shows her cousin a photo to give her a glimpse at what Peter looks like, and we can see that it's that same lock screen as it was in the first film — an image of her cuddling with Peter.

Considering not much time seems to have passed from the first movie to the second one, it isn't too surprising that Lara Jean hasn't changed up the lock-screen photo on her phone.

It may look like that photo was a staged between Lara Jean and Peter, but it's actually a candid shot that was taken by a crew member, the first film's director Susan Johnson told Entertainment Tonight.

She said that Condor and Centineo fell asleep on the couch in the green room during filming, and someone "just stood over them and took that picture."

Fisher confirmed on Twitter that he actually wrote and sealed the letter that his character, John Ambrose, sent to Lara Jean.

Throughout most of the first film, Kitty is seen wearing a gold-plated "Feminist" necklace that she told Vulture was an important part of Kitty's personality.

You can spot her wearing it throughout the second film, too.

The sequel features Lara Jean and Peter celebrating their first Valentine's Day together, and a school tradition is sending a capella group students around to serenade people.

The first a capella song that's performed is actually Billie Eilish's "Ocean Eyes," the titular track from her 2016 album.

The other song the group sang was the Backstreet Boy's classic track "I Want It That Way."

Fans of "Dance Moms" alum and dancer Maddie Ziegler will be thrilled to see that the star made a cameo in the film.

Ziegler appeared behind Lara Jean as she was watching a group of students serenade a couple for Valentine's Day.

Dressed as a cheerleader, she tapped Lara Jean and said, "Get ready, Lara Jean. Last year, Peter sent [a seranade] to Gen every period."

Although it was very quick, this line set the stage for some of the doubts Lara Jean began to have about Peter.

Peter and Lara Jean exchange Valentine's Day gifts on the track in the spot where Peter first showed her the letter she wrote about him.

They also kiss on the track, which is where they had their very first kiss. Just like in the first movie, students jog by them as they're kissing.

At one point, Lara Jean and Peter are in a science class dissecting an octopus. Even though it seems every student in the class has goggles on, these two are not practicing lab safety.

Interestingly, there is a pair of goggles sitting on the table in front of them.

In one dreamy scene, Lara Jean walks in on John Ambrose playing the piano, and it's clear that he's a very talented musician.

And although actors are often just pretending to play instruments on-screen, that wasn't the case here: Fisher tweeted that that was actually him playing the piano.

"It's a very tough scene to film," Fisher previously told Insider. "And, frankly, it was very late in the night when we filmed it, and having to play the piano and improvise and also film a scene at the same time was difficult."

Andrew Bachelor, who goes by King Bach, played Gabe Rivera, Peter's good friend and teammate, in the first film — but he was entirely missing from the sequel.

Instead, Peter's new main pal was Trevor Pike, played by Ross Butler.

Toward the end of the film, Lara Jean has a makeover sequence to get ready for the ball at Belleview.

If this scene felt kind of familiar, it may be because it has parallels to recent versions of Cinderella.

Stormy (Holland Taylor) was sort of like a fairy godmother in how she prepared Lara Jean for the ball by giving her a makeover and a gown.

Plus, as Cinderella does in many variations of the tale, Lara Jean is also wearing a blue dress. And, of course, there's the iconic reveal when Lara Jean walks down the grand staircase — which was one of Condor's favorite scenes.

Condor told Teen Vogue, "I've never had a Cinderella moment nor have I seen, besides I think 'Crazy Rich Asians,' an Asian Cinderella moment, where she's walking down the stairs, and it's beautiful, and you're like, 'Holy crap.'"

Toward the beginning of the film, Peter and Lara Jean go on a date to a carnival and Lara Jean wins a snow globe from one of the games.

Inside the trinket, snow falls around a little statue of a couple kissing. Later in the film, this scene seems to be recreated by Lara Jean and John Ambrose, who end up kissing in the snow (even though it's late in the season for it).

In the beginning of the film, the pair promised not to break each other's hearts — and when Peter came to win Lara Jean back, he said: "Break my heart into a thousand pieces."

This is actually Centineo's favorite line, and he said it's because it brings the movie full circle.

"I love the line because that is the destruction of a promise that started the film. We promised not to break each other's hearts," he told Fox News.

He added, "And then the meaning of 'break my heart' has become a transcendence of that original promise that was really the impetus for the problem of the entire film. We don't wanna break each other's hearts; we're not telling each other things."

Fans of Jenny Han's novel "P.S. I Still Love You" (which inspired the film) will notice many differences between the book and the movie.

First of all, Peter and Lara Jean's first date is different. In the book, they watch a movie and have fried chicken at Peter's favorite restaurant, Biscuit Soul Food. In the movie, they go to an Italian restaurant and a lantern festival.

Another huge difference is that, in the book, Lara Jean and John Ambrose are pen pals; They don't volunteer together at Belleview.

Read More:

• 14 movies to watch if you love the 'To All the Boys' series
• 15 things you probably didn't know about 'To All the Boys I've Loved Before'
• Jordan Fisher stars in the 'To All the Boys' sequel as John Ambrose. Here are 5 things to know about him.