Pen reveals to Scarlett at her birthday party that she and Lukas have an incompatible sex life.

Scarlett and Pen meet for coffee and discover they share a mutual interest in BDSM.

At Coach Sima's party, Pen drunkenly reveals she broke up with Lukas and pushes Scarlett to sleep with him.

Lukas sends Scarlett an email suggesting they start a sexual relationship whenever she feels ready.

Scarlett reports to Dr. Smith's lab and discovers Lukas is the other undergraduate research assistant on the team.

Scarlett and Lukas exchange their completed BDSM checklists at the library and share a passionate kiss.

Lukas initiates oral sex with Scarlett for the first time in the science lab.

Scarlett confronts Lukas about ignoring her; he apologizes and admits he was afraid of how much he wanted her.

Lukas shares his STI test results with Scarlett and they have penetrative sex for the first time.

Scarlett spots her high school diving coach in the crowd at a meet, feigns illness, and flees the aquatic center.

Scarlett breaks down crying and tells Lukas about her father violating his restraining order, Josh's breakup call, and getting the twisties.

Scarlett wakes Lukas in the middle of the night and performs the inward dive for the first time in two years.

Scarlett wins first place at the NCAA championships after the best competition of her career.

Pen bursts into the locker room after the NCAA and accuses Scarlett of stealing her boyfriend and her medal.

Scarlett travels to Sweden, where she and Lukas profess their love and agree to build a life together.

Scarlett Vandermeer returns to Stanford still haunted by the injury she sustained at the NCAA championships two years earlier, struggling to reclaim her identity as an elite diver and premed student. When her diving captain Pen reveals that she and her boyfriend Lukas have incompatible sexual preferences, a chain of events begins that slowly draws Scarlett and Lukas together. After exchanging BDSM checklists and beginning a careful, communicative sexual relationship, the two grow closer while Scarlett continues to battle her mental block in the pool. A pivotal night where Scarlett confesses her trauma to Lukas — her abusive father's contact and an ex's breakup call on the eve of her injury — finally unlocks her ability to perform the inward dive she has avoided for two years. Scarlett goes on to win the NCAA championships, but a confrontation with Pen in the locker room forces her to seek distance and perspective. After reconciling with Pen and flying to Sweden, Scarlett and Lukas confess their love and commit to a shared future.

The central romance and athletic arc from start to finish.

Scarlett begins therapy with Sam, describing five of the six main dives and carefully avoiding the one that injured her.

Scarlett interrupts a heated argument between Pen and Lukas at the aquatic center before diving practice.

Lukas helps Scarlett after she gets locked out of the locker room and openly acknowledges their shared BDSM interests.

Professor Dr. Carlsen tells Scarlett her paper was the best in class and invites her to join a biology research project.

Coach Sima tells Scarlett that Victoria is out for the season and asks her to become Pen's synchronized diving partner.

Scarlett takes the MCAT and attends a party where Pen reveals she has started dating her former teaching assistant Theo.

Lukas hands Scarlett a BDSM checklist to fill out independently; Scarlett and Pen have their first synchro practice together.

Scarlett meets Lukas's roommate Hasan at his apartment, and she and Lukas engage in sexual foreplay for the first time.

At an afterparty, Lukas interrupts an uncomfortable encounter with another swimmer and apologizes to Scarlett for failing to communicate.

After spending the night together, Scarlett and Lukas share breakfast and discuss Swedish culture and his family.

Scarlett watches old competition videos of Lukas online and researches Swedish words he has been teaching her.

At the championship qualifiers, diver Carissa approaches Scarlett and warns her not to trust Pen.

Scarlett learns Pen reported Carissa's abusive mother years ago and publicly defends Pen against Carissa's ongoing harassment.

Scarlett and Lukas explore the streets of Amsterdam together before the World Aquatics competition begins.

Scarlett and Pen get matching henna tattoos before a diving event, and the team qualifies for the NCAA championships.

While the central romance unfolds, Scarlett's daily life at Stanford is shaped by a series of significant moments that reveal her growth, her relationships, and the pressures she faces as a student-athlete. She begins therapy with a new counselor, gets pulled into a biology research project, and is asked to take on the demanding role of Pen's synchronized diving partner. As her relationship with Lukas deepens through shared meals, hikes, and late nights, Scarlett also navigates social friction — including a competitive swimmer at an afterparty and a hostile rival diver at the championship qualifiers who threatens Pen's reputation. Defending Pen against false accusations marks a turning point in their friendship, showing Scarlett's growing confidence and loyalty. By the time Scarlett walks the streets of Amsterdam with Lukas before World Aquatics, she has quietly transformed from someone who pushed the world away into someone willing to show up for the people she loves.

The supporting moments that built Scarlett's world at Stanford.

After Lukas leaves the aquatic center, Pen tells the group she is considering breaking up with him over their BDSM incompatibility.

During a therapy session, Sam asks about Scarlett's mental block and Scarlett admits it is the first one she has ever experienced.

At practice, Scarlett attempts the inward dive but accidentally performs a back tuck instead, exposing the depth of her mental block.

At a party, Scarlett nearly walks away from Lukas entirely but then texts him asking where and when to meet.

After reading Scarlett's BDSM list, Lukas tells her he wants everything on it but leaves before showing her his own.

Pen tells Scarlett she already knew she and Lukas would be sexually compatible and gives her blessing for their relationship.

On a hike with Lukas and his brother Jan, Scarlett realizes Lukas has been withdrawing after sex to deny himself pleasure.

Lukas opens up to Scarlett about his mother dying when he was fourteen and how swimming became his way of coping.

Lukas and Scarlett open her MCAT results together and discover she scored a point higher than Lukas did.

During therapy, Scarlett has a breakthrough and admits her deepest fear is attempting something and failing to be perfect.

In Amsterdam, Lukas reveals he will not defer his medical school acceptance to compete in the Olympics another year.

Lukas professes his love to Scarlett in Swedish during sex; immediately afterward, Pen calls with news of a positive doping test.

Pen's doping test is confirmed to be a false positive, ending the crisis before the NCAA championships.

Lukas declares his love for Scarlett in front of the team; Scarlett invokes their safe word and asks him for space.

Pen arrives unexpectedly at Scarlett's home in St. Louis and apologizes in person, and the two friends reconcile.

Beneath the surface of Scarlett's junior year lies a series of quiet but decisive moments — realizations, confessions, and choices — that steer both the romance and her personal healing. From the night Pen first names the BDSM incompatibility that will set everything in motion, to Scarlett's hesitation before finally texting Lukas to meet, each turning point reveals her inching closer to honesty about what she wants. Lukas's own revelations — about his grief over his mother, his plan to leave competitive swimming, and his love for Scarlett — repeatedly force her to confront the depth of what they have built together. Breakthroughs in therapy and at the pool mark her internal progress, while crises like a false doping positive and a public confrontation test whether she can hold onto herself under pressure. By the time Pen arrives unannounced to make amends, Scarlett has learned to protect her needs, forgive with clarity, and reach toward the future she truly wants.