"Shigatsu wa Kimi no Uso: Moments" centers on Kōsei Arima, a former child prodigy pianist who loses his ability to hear the sound of his piano after the death of his emotionally demanding mother, Saki Arima. Traumatized by her passing and the pressure she placed on him, Kōsei withdraws from performing and lives a monotonous life, disconnected from music. His childhood friends, Tsubaki Sawabe and Ryōta Watari, remain close, though Kōsei struggles to reconnect with his passion.

The story takes a pivotal turn when Kōsei meets Kaori Miyazono, a free-spirited and talented violinist whose unconventional approach to music contrasts sharply with Kōsei’s rigid, technical style. Kaori’s vibrant personality and insistence on playing music with raw emotion reignite Kōsei’s interest in performing. She encourages him to return to the piano, helping him confront his past and rediscover the joy of music. As Kōsei begins to perform again, he gradually overcomes his emotional barriers, though his journey is fraught with challenges and self-doubt.

Kaori’s own struggles are revealed as the narrative progresses. Despite her seemingly carefree demeanor, she battles a serious illness that threatens her ability to play the violin and her life. Her determination to live fully and express herself through music inspires Kōsei and those around her. The relationship between Kōsei and Kaori deepens, blending themes of love, loss, and the transformative power of art.

The series explores the lives of its supporting characters as well. Tsubaki, a childhood friend of Kōsei, grapples with her feelings for him, struggling to reconcile her role as a friend with her growing romantic emotions. Ryōta, a popular and athletic classmate, provides a grounded perspective, often mediating between Kōsei and Tsubaki. Emi Igawa and Takeshi Aiza, rival pianists who admire Kōsei’s talent, also play significant roles, challenging him to grow and pushing him to confront his insecurities.

The narrative is structured around Kōsei’s performances, each serving as a milestone in his emotional and artistic development. Music becomes a central metaphor for the characters’ inner lives, with performances reflecting their struggles, hopes, and connections to one another. The series culminates in a poignant exploration of legacy, as Kōsei and Kaori’s shared experiences leave a lasting impact on their lives and those around them.