Seventeen-year-old Phil, Louis Hofmann, returns home from summer camp to the secluded Villa Visible—a sprawling old mansion where he lives with his mother, Glass Sabine Timoteo, and his twin sister, Dianne Ada Philine Stappenbeck. The family, seen by the nearby community as eccentric, keeps to themselves, rarely engaging with neighbors, yet they share a warm bond with their lesbian friends, Tereza Inka Friedrich and Pascal Nina Proll. Dianne is said to communicate with animals, a rumor that hints at a mysterious, sensitive side within the house.
Upon his return, Phil discovers a hurricane has ravaged the surrounding area, tearing at the garden and leaving the villa’s interior rattled. He also senses a growing rift between Glass and Dianne, who now barely speak to each other—or to him. He spends the remainder of the summer in the company of his eccentric best friend, Kat Svenja Jung.
When school resumes, Phil is drawn to Nicholas Jannik Schümann, and the two begin a passionate, secretive affair. The situation feels unusually open: Nicholas even befriends Tereza’s cabin for stolen moments of privacy, while Kat’s easeful dynamic with the pair gives the trio a carefree rhythm. Yet Phil starts to doubt Nicholas’s sincerity. To prove his devotion, Nicholas shows Phil a shed where he collects discarded objects. Reigniting his feelings, Phil crafts a display case for Nicholas in the workshop of Michael Sascha Alexander Geršak. But the fragile trust shatters when Phil discovers Nicholas and Kat asleep together. Nicholas insists he needs both Phil and Kat, but Phil cannot accept it and rejects him.
Phil notices Dianne sneaking out nightly and follows her to a hospital. Confronting Glass about their rift, he learns nothing of what transpired during his absence. As familial tensions escalate, Phil moves in with Tereza, followed shortly by Dianne.
Flashbacks reveal the family’s troubled past: Glass arrived in Germany pregnant from America, never disclosing the twins’ father’s identity. Her string of failed relationships, often sabotaged by her own behavior, left Dianne longing for a paternal figure. A miscarriage—nearly fatal for Glass—further strained their history. Glass hints that a botanical book in the villa’s library holds answers to their conflict. Phil recalls tales of medieval women using belladonna poison to enhance allure, then lethal doses to “erase their mistakes.” Finding the book in Dianne’s room, he learns she poisoned Glass in revenge for driving away her partners. During Phil’s absence, Dianne’s boyfriend was left comatose after a storm-induced accident, destabilizing her. Her confession to Glass caused the family’s estrangement. With Michael’s help, Phil reconciles Dianne and Glass, reuniting the family.
After ending things with Nicholas, Phil realizes his family is his “center of the world”—a concept Glass once explained varies for everyone. He decides to travel to the U.S. to seek his father, whom Glass describes as a good man she abandoned. Before departing, she whispers his father’s name to him.
