In episode two, it's revealed Jeremiah (Gavin Casalegno) is sexually fluid when he points out multiple people he's made out with at the pool. "I just like to kiss and be cozy with people," he explains. In episode three, he hooks up with a guy named Luke before fully realizing his romantic feelings for Belly (Lola Tung).
"It felt right for the character and right for the moment," showrunner and author Jenny Han explained to E! News of her decision to make Jeremiah sexually fluid. "I think for younger generations there's less of a binary and they're just more relaxed about sex and people's identities and it doesn't have to be one or the other. That felt like a place where we could reimagine one of the main characters in a way that was really organic. That character is someone who has always been really comfortable in his own skin."
While Han acknowledged "some people might be surprised" by the revelation, she stressed that "if you look at the books and look at the character, it shouldn't feel like too much of a surprise."
Casalegno added "it was really fun to explore Jeremiah's side of the story" in the series and "bring different sides of him to the screen."
One of the unexpected highlights of the adaptation is the infusion of more of the friendship between the moms, Laurel (Jackie Chung) and Susannah (Rachel Blanchard), pot-smoking sessions, one night stands and tear-filled fights included. Their bond is series' strongest storylines as they both come to terms with Susannah's cancer diagnosis.
The series also expands each of the women's worlds, with Laurel struggling to write her next novel and dealing with her ex-husband visiting with his new younger girlfriend (Belly and Steven's dad did come to Cousins in the book) and Susannah is now an artist, who is working on portraits of each of the kids throughout the summer.
We especially love the amped-up presence of Laurel and Susannah because it offers a relationship for original readers, who are now more than a decade older, to connect to for where they are now in their lives, while also wistfully remembering the summers of their youth through Belly. Now that's what we call a win-win!
A new character who plays an integral role in the series is bestselling Brooklynite novelist Cleveland (Alfredo Narciso), who becomes Laurel's love interest and a surprising outlet for Conrad (Christopher Briney) to express his feelings, giving audiences insight into the brooding teenager's inner turmoil that they didn't have access to in the book.
"You have to open up the world and justify people's lives a little more, so having Conrad have a whole mentor in Cleveland was wonderful as an actor as understanding his journey and where he comes from," Briney said. "Because in the books, I was still enthralled obviously, but you don't really know where or why or how he changes. To get some justifications and to be able to watch some of it and act some of it, I really appreciated."
While Belly's older brother Steven is mostly M.I.A. from the book after he decides to spend most of the summer doing college tours with his dad, the TV series gives the sidelined sibling his own love interest in fashionable debutante Shayla (Minnie Mills). Their storyline explores the class differences and racial biases Steven experiences while working at the country club in the community.
"Jenny Han and the entire writing team were very, very awesome with giving Steven new breath and new life and allowing me to step into that," Sean Kaufman said. "It just felt really cool to get a character I could sink my teeth into and take that bite into."
Come on, is it really a teen drama without a major event that the entire season builds up to?
For the show, Han crafted the debutante ball, which Susannah convinces Belly to participate in. In addition to opening up the world of Cousins Beach and serving as the entry point for many of the new supporting characters, the deb ball also serves as the new setting for Conrad and Jeremiah's emotional fight, which took place on the beach in the books. Plus, it's where Belly and Conrad have their epic dance, set to Taylor Swift's "The Way I Loved You (Taylor's Version)."
"It's so magical and it was magical to film and just everything came together perfectly," Tung said of the scene. "That was my favorite moment."
While in the book Susannah ultimately decides not to pursue treatment after her cancer returns, Han chose a different direction for the show. In the finale, the devastated brothers beg their mom to do it for them and, after some slight hesitation, she agrees. The change could potentially have a significant impact on season two as—spoiler alert!—Susannah dies between books one and two.
Readers of the series know the book begins and ends with the same scene: One of the boys—who is revealed to be Conrad in the final chapter—unexpectedly coming to visit Belly in the winter.
The glimpse at the future isn't in the series, which ends with Conrad and Belly kissing on the beach...after she previously decided to be with Jeremiah. It's going to be a cruel summer (plus a few more seasons) waiting to see how this plays out.
Like the books, Belly's BFF is the outspoken and pretty queen bee Taylor (Rain Spencer), who encourages Belly to break out of her shell only to feel threatened when she begins to take some of her spotlight. While the two have a falling out after Belly catches Taylor making out with her older brother Steven when she visits Cousins, the very relatable teen scandal actually happens in a flashback set two summers prior in the book.
In the series, Taylor's visit is still just as dramatic (including the kiss with Steven), but she gets the chance to redeem herself in the series when the character returns in the final two episodes to help Belly sort out her love life—she is firmly Team Jeremiah, by the way—and to help her win a charity volleyball game. Growth, we love to see it.
OK, not exactly a major change but can we just acknowledge that the series' version of Cameron (David Iacono), Belly's former classmate-turned-sweet-summer-romance, is 1,000-times better than he is in the book? Imagine a nerdier, vegan and straight-edge Seth Cohen, who can speak Latin, works on a whaling boat and takes you to a drive-in movie. How dare Belly break up with him?! Justice for Cam Cameron!