In a remote forest, two young girls, Alma and Alex, live with their mother inside an abandoned hotel that feels cut off from the outside world. The woman has raised them with a stark belief: humanity may have vanished, and survival hinges on staying apart from others forever. She teaches them about medicinal plants, enforces strict routines, and forbids going outside during the day because she claims the sun could kill them. The arrangement feels peaceful at first, a sheltered life built on careful rules and close knit routines, but it also casts a perpetual shadow over their childhood.
As Alma and Alex grow older, the bonds of obedience begin to fray. The sisters start to question their mother’s lessons about civilization, danger, and even their own sexuality, a process that intensifies when Alma experiences her first period. The once-harmonious dynamic between the girls becomes strained, and the sisters quietly seek ways to understand the world beyond their locked doors. Their curiosity leads them to secretly enter a forbidden warehouse where the mother has warned them never to go. Inside, they uncover unfamiliar objects—a phone, a pornographic magazine—things that expose them to ideas and images about the male body that were previously beyond their reach.
With time, Alex grows increasingly restless under their mother’s control while Alma remains slightly more compliant, and their disagreements grow louder. The mother clings to childhood habits, even writing messages intended to intercept any surviving humans, a ritual that underscores her isolation and fear. Alex longs for independence and a connection to anything beyond their secluded life, and her growing unease fuels Alma’s lingering nightmares about the world outside. The tension peaks one morning when Alma believes Alex has left, only to realize she is still there, prompting Alma to step outside during the day—an act that infuriates their mother and deepens the rift between the sisters and their guardian.
The rift widens when Alex persuades Alma that their mother can no longer be trusted. She convinces Alma to send a “message in a bottle” across the black river, a boundary the mother has warned them never to cross. The mother discovers their plan, punishes them by locking them in their room, and the days stretch as they remain sealed away. When a long confinement finally breaks, the sisters seize a chance to escape and begin a new exploration of the estate, uncovering the comforts their mother had concealed from them. Enraged yet driven, they leave the house behind and wander into unfamiliar spaces, with Alma later regretting the choice and pleading for a return home. A fierce argument with Alex follows, and Alex bolts away while Alma, frightened, falls and sustains a foot injury, which the mother tends to when she finds Alma and brings her back.
Time drags on as Alma feels increasingly drained while the mother grows more repressive. A creeping sense that something is seriously wrong settles in. When Alma attempts to swap her tea with her mother’s, the mother falls into a deep sleep, giving Alma a rare chance to test the outside world during the day. The attempt confirms that many of the mother’s stories were not true. Confronted by this truth, Alma decides to leave as the mother confronts her after waking. A violent struggle erupts, and Alma escapes into the woods, with the mother chasing after her. The mother’s pursuit ends when she slips, falling into a hole and sustaining a fatal injury. Before dying, the mother points Alma toward a path that reveals the truth, guiding her toward what lies beyond their island of isolation.
On the path ahead, Alma discovers Alex waiting at the edge of a river, and Alex appears to know what happened all along, rescuing Alma from drowning. They stumble upon an abandoned car, and Alma begins to piece together a memory she hadn’t fully understood: an accident from her very early childhood. She recalls being kidnapped by a woman who was not her mother, and the revelation forces Alma to confront a painful realization—that she had created the alternate persona of Alex as a coping mechanism for loneliness. With this haunting discovery, Alma stands alone at the threshold of a society she has never truly known, facing a future that will require her to build a life beyond the shelter of the forest and the secrets of her past.
