At age five, Ellie cannonballs into a pool and splashes other swimmers, earning the cruel nickname 'Splash.'

Ellie creates self-imposed 'Fat Girl Rules' to cope with bullying, built around making herself as small as possible.

Ellie's best friend Viv moves to Indiana, leaving Ellie without her closest companion at the start of a new school year.

A new girl named Catalina moves next door, and she and Ellie bond over their shared love of words and music.

Ellie's first therapy session with Dr. Wood feels like a power struggle as she refuses to share anything about herself.

Dad takes Ellie to a plus-size boutique, and she tries on clothes made for her body, first likening herself to a starfish.

Bully Kortnee unscrews Ellie's desk at school, causing it to collapse while classmates swarm and mock her.

Dad surprises the family with a trip to Niagara Falls, where tourists laugh at Ellie and photograph her without permission.

Ellie confronts bully Enemy Number 3 in the school hallway and realizes she has begun to claim her right to take up space.

Marissa and Kortnee capture Ellie's dog Gigi and demand she eat a whale-shaped cake on video as ransom.

Backed by Catalina, Catalina's siblings, and Anaïs, Ellie throws the ransom cake in the bullies' faces and reclaims Gigi.

Mom secretly takes Ellie to a bariatric surgeon without telling Dad; Ellie refuses the consultation and walks out.

During a family therapy session, Ellie discards her prepared statement and instead speaks honestly about Mom's conditional love.

Ellie gives Mom a notebook containing every hurtful thing she has ever said, and Mom collapses in realization.

Ellie swims freely with Viv and Catalina in the family pool, resolving never to make herself small again.

Twelve-year-old Ellie's story begins with a childhood pool incident that earns her the cruel nickname 'Splash' and sets off years of relentless bullying. She develops self-imposed Fat Girl Rules to survive, shrinking herself to avoid attention, while her mother's fixation on her weight deepens her shame at home. A new friendship with neighbor Catalina and reluctant therapy sessions with Dr. Wood slowly help Ellie recognize her own worth. Key confrontations with school bullies and her controlling mother force her to use her voice and stand firmly in her own defense. After rescuing her dog from her bullies and facing her mother in a family therapy session, Ellie delivers a powerful reckoning with the abuse she has endured. By the final scene, she swims freely with her two best friends, fully resolved to take up space in the world like a starfish.

Ellie's core journey from shame to self-acceptance.

Ellie and Viv dance freely in the backyard together before Viv moves away, sharing a moment of uninhibited joy.

Ellie discovers her parents have arranged therapy sessions for her without her knowledge, feeling betrayed by Dad.

On the first day of school, bullies Marissa, Kortnee, and Enemy Number 3 immediately target Ellie with cruel comments.

Dr. Wood brings her dog to a session; when Ellie notices a photo of Dr. Wood with diverse friends, she decides to trust her.

Mom withholds food from Ellie, monitors her trash for diet violations, and denies her piano lessons until she loses weight.

Catalina invites Ellie to get frozen custard with her family; both girls face prejudice from strangers at the restaurant.

At a family dinner, a young boy tells Ellie she is fat; Dad demands an apology but Mom rushes the family out.

Ellie accidentally reads hateful journal entries Liam wrote about her, then burns the pages in the backyard to release her anger.

Ellie chooses a misunderstood whale as her school project subject, and her English teacher tells her she is officially a poet.

Ellie confides in Catalina about her missing bedroom mirror, explaining that Mom once stood her before a mirror and named her flaws.

Mom and Dad give Ellie birthday tickets to visit Viv in Indiana.

Ellie spends Thanksgiving at Catalina's house and experiences the warmth and unconditional acceptance of her family for the first time.

Ellie delivers a book report connecting the misunderstood whale's story to her own, looking directly at bully Kortnee as she speaks.

Paired with Enemy Number 3 for a library display on bullying, Ellie discovers that he is bullied for his economic hardship.

Ellie notices a whale mural in her hometown and, for the first time, sees the whales' beauty and connects it to herself.

These events reveal the everyday textures of Ellie's life, from dancing with Viv before she moves away to enduring her first brutal day of school bullying. Ellie's family dynamics come into focus through her mother's controlling food rules, her brother's recorded hatred, and the warmth of Catalina's unconditionally welcoming family. Small but significant milestones include Ellie earning a therapist's trust, uncovering the truth about a bully's own vulnerability, and receiving birthday tickets to visit her best friend. A pivotal book report and a quiet encounter with a whale mural round out Ellie's gradual transformation. Together, these moments build the emotional scaffolding that supports Ellie's growth from beginning to end.

The supporting moments that shape Ellie's world and relationships.

Ellie investigates Catalina and learns she does not attend her school or know its bullies, deciding Catalina is safe to trust.

Mom alludes to bariatric surgery for Ellie; a worried Dad privately promises that he will never let the surgery happen.

Enemy Number 3 trips over a broken shoe sole and, catching Ellie watching, immediately hurls an insult at her to save face.

Dr. Wood encourages Ellie to draw or write others' hurtful words, explaining that expressing them will help release the pain they cause.

Marissa and Kortnee deliberately tear Ellie's shirt in gym class; Ellie retaliates with insults and feels deeply miserable afterward.

Dr. Wood helps Ellie understand that retaliating with insults is attacking rather than self-defense, and that better approaches exist.

Liam abandons Ellie to take the public bus; strangers harass her until Catalina and her siblings find her safe during a tornado.

After Ellie tells Catalina that Mom thinks something is wrong with her, Catalina suggests the real problem is Mom's thinking.

Ellie writes an open letter to the tourists who mocked her at Niagara Falls, expressing her humiliation and why it was wrong.

Anaïs apologizes to Ellie for her years of passivity and for originally coining the nickname 'Splash,' and the sisters fully reconcile.

Dr. Wood helps Ellie realize she allows mistreatment because Mom has taught her that she deserves to be treated poorly.

Ellie hands Dr. Wood her written Fat Girl Rules to read, a significant act of trust toward her therapist.

Catalina gives Ellie a mirror as a Hanukkah gift, and Ellie weeps as she recognizes her own beauty for the first time.

Ellie burns her Fat Girl Rules; separately, Dr. Wood writes Mom's harmful food rules on a whiteboard for Ellie to erase.

Dad apologizes to Ellie for not protecting her from Mom's cruelty, and Ellie ultimately finds a doctor who treats her with respect.

This pool traces the internal shifts and revelations that drive Ellie's emotional arc. Early discoveries—learning that Catalina is genuinely safe and that her mother is quietly pursuing surgery—establish the emotional stakes of her journey. As Ellie begins to assert herself, Dr. Wood guides her through crucial lessons about expressing pain, the difference between retaliation and self-defense, and why she has allowed mistreatment for so long. Catalina's mirror gift and the erasure of the Fat Girl Rules mark the story's deepest turning points. The pool closes on Ellie and her father finding a doctor who respects her, confirming that she has fully claimed her right to be treated with dignity.