In Seoul, during the year 1994, we meet Eun-hee, a quiet 14-year-old girl from a working-class background who is on the verge of starting high school. She has a passion for drawing and enjoys spending time with her best friend, Ji-hu Park, as they attend cram school together. Eun-hee is secretly dating her boyfriend, Ji-wan, who holds a special place in her heart. Meanwhile, her parents, especially her father, often overlook her emotional needs, focusing instead on her older brother, who mistreats her both physically and verbally. Her older sister faces similar neglect and abuse.
At cram school, Eun-hee's life takes a turn when she meets Ms. Kim, her new free-spirited Chinese teacher, with whom she forms an instant connection. On a fun night out dancing with Ji-hu Park, she encounters Yu-ri, another schoolgirl who seems to have a crush on her, leading to a budding friendship.
However, the fabric of Eun-hee's life begins to unravel. After discovering a lump behind her ear that requires surgical intervention, her world grows increasingly complicated. A tense moment arises when she gets caught shoplifting alongside Ji-hu Park. Out of fear, her friend reveals her identity to their parents, resulting in severe repercussions for Eun-hee. Later, when Eun-hee confronts Ji-hu Park about this betrayal, things remain unresolved as apologies are not made. Subsequently, Ji-wan is forced into breaking up with her after his affluent mother learns about Eun-hee's lower social standing, leaving her heartbroken. Yet, amidst all this turmoil, Ms. Kim encourages Eun-hee to hold onto her spirit and keep moving forward.
As Eun-hee prepares for surgery, her father unexpectedly breaks down, revealing his true concern and love for her, a moment of vulnerability that catches her off guard. The surgery goes smoothly, and she reconciles with Ji-hu Park after her friend admits her fears led to the betrayal. Ms. Kim and Yu-ri come to visit her in the hospital, sharing emotional support. Ms. Kim announces her plans to leave the cram school but promises to stay in touch, while Yu-ri confesses her feelings, leading to a gentle kiss on Eun-hee's cheek.
Determined to bid farewell to Ms. Kim, Eun-hee mistakenly arrives too late due to a mishap with another teacher, plunging her into despair. In a confrontation at home that night, she argues with her parents about their treatment of her, even criticizing her brother's academic failures despite his special care. In a fit of rage, he hits Eun-hee, causing serious injury; the doctor suggests pressing charges, but her resolve falters. As the new semester rolls in, she tries to reconnect with Yu-ri, only to discover that Yu-ri has moved on from her feelings. This revelation leaves Eun-hee confused, especially when Ji-hu Park shares that she, too, is dealing with family strife.
All of this culminates in a tragic event when the Seongsu Bridge collapses. With her sister involved in the incident, Eun-hee fears the worst but learns that her sister survived due to a delay. Her brother, too, breaks into tears from relief, showcasing that his tough exterior hides a deep-rooted care for his family. However, Eun-hee brushes off Ji-wan's attempts to mend their relationship, claiming that her feelings for him have vanished.
In a poignant twist of fate, she receives a package from Ms. Kim, filled with a letter and a sketchbook, just as she sets out to express her gratitude in person. Tragically, she learns that Ms. Kim perished in the bridge collapse. Heartbroken, she reflects on her family dynamics while discussing their lost uncle with her mother. They bond over the shared grief, which deepens Eun-hee's understanding of loss.
Eventually, Eun-hee and her siblings visit the site of the devastating collapse. Overcome with emotion, she faces her grief, finally accepting it. The following morning brings a new dawn, as the family shares breakfast together, treating each sibling equally, a stark contrast to their earlier neglect. Armed with renewed strength, Eun-hee reads Ms. Kim's final heartfelt letter. It reassures her that while bad experiences exist, good ones will always follow. Standing alone in the schoolyard, she reflects on her growth — now mature and at peace with her journey.
