In the cutthroat world of a prestigious arts academy, two gifted pianist sisters find their bond tested by a sinister discovery in the haunting horror-thriller Nocturne. Sydney Sweeney stars as Juliet, the shy and overshadowed twin, who watches her more charismatic sister, Vivian (Madison Iseman), command the spotlight. When a troubled classmate’s mysterious notebook falls into Juliet’s possession, its cryptic contents promise a path to extraordinary talent and a chance to finally outshine her sister. As she delves deeper into the notebook’s dark secrets, Juliet’s pursuit of musical perfection spirals into a terrifying obsession, straining her relationship with Vivian and attracting the attention of a charismatic teacher (Ivan Shaw) and a fellow student (Jacques Colimon). Directed and written by Zu Quirke, the film crafts a chilling atmosphere of psychological dread and supernatural mystery, where ambition blurs with madness and every note played could come at a deadly price.