How 'The Summer I Turned Pretty' season 2 might end, based on the book series

• "The Summer I Turned Pretty" season two premieres on Friday.
• The ending of the first season didn't exactly stay true to the book it was based on.

"The Summer I Turned Pretty" season one ends on the beach in Cousins, with Conrad Fisher (Christopher Briney) declaring his desire for Belly Conklin (Lola Tung). The two share a kiss set to "This Love" from Taylor Swift's upcoming album "1989 (Taylor's Version)."

"In this moment, I realized if this can happen, maybe anything can," Belly says in a voiceover that plays over the kiss.

The TV adaptation's ending was quite different from the ending of Jenny Han's original story.

Belly and Conrad do kiss in the book, but it's not the final scene. Plus, Conrad pulls away from Belly in the book because he doesn't want them to start a relationship right after his mom revealed her cancer relapse.

The first book in Han's trilogy instead ends with a flashback that takes place in December. Belly gets in the car with a mystery boy (presumed to be either Conrad or her other prominent love interest in the series, Conrad's brother Jeremiah, played by Gavin Casalegno). Belly and the boy are headed to a mystery location, presumed to be their shared beach house at Cousins Beach.

Despite the differing endings, the first season of the show respected the essence of Belly's love story from the books. But you might be wondering how season two of "The Summer I Turned Pretty" will end if it stays true to the book it's based on, "It's Not Summer Without You," which is the second book in the trilogy.

Well, there are two possibilities, since it kind of has two separate endings.

Warning: Book spoilers ahead.

If the season ends with the book's 'present-day' ending, we might see Belly finally let go of Conrad

From the trailer, we know that the second season takes place after the death of Conrad and Jeremiah's mother Susanna (Rachel Blanchard), just as book two does. Part of Belly's summer in season two, based on the book's plot summary and the season two trailer, will likely be dedicated to convincing stubborn adults that the house in Cousins is too magical to sell.

If the series stays true to the events of the second book, the final scenes of season two could see Belly in a hotel room with Jeremiah and Conrad waiting out the rain during a road trip. In the book, Conrad's quest to save his mom's summer house doesn't ruin his GPA, but he's left bitter after witnessing a kiss Belly and Jeremiah shared while they waited for him to finish a final exam.

In the book, after being nasty to Jeremiah and Belly, Conrad lays awake with Belly in their shared hotel room while an oblivious Jeremiah sleeps. He apologizes to Belly for acting like their relationship never mattered to him all day.

But in the morning, he isn't able to make eye contact with Belly, prompting her to believe he really doesn't care about her. If the show stays true to the books, in that moment Belly might vow to let her love for Conrad go forever.

She'll leave the hotel with Jeremiah, and hold hands with him for the whole car ride home, as she does in "It's Not Summer Without You."

If the season ends with the book's flash-forward ending, Belly might end the season in a white dress with a mystery man

The hotel scene described above isn't the actual final scene in "It's Not Summer Without You." Han is also the creator of the TV series, so she might decide to stay true to her book's original ending.

In that ending, there's a flash forward to "a couple of years later," where Belly is on the beach in a white dress with a mystery man.

"This wasn't how I pictured my future. Me, in a white dress in the pouring rain running for the car," Belly thinks in the book. "Him running ahead of me and opening the passenger door."

The mystery man then asks Belly, "Are you sure?"

Belly replies no, and the book ends on that cliffhanger, suggesting her future is uncertain.

"The Summer I Turned Pretty" season two will premiere its first three episodes on Prime Video on Friday.