The ending of Marshmallow reveals that the creepy, murderous "doctor" haunting the camp isn’t a ghost or a supernatural being, but rather a manufactured entity created by the camp's sinister experiment. Throughout the film, Morgan and his friends discover that the children at the camp, including those who seem to be possessed or controlled by the doctor, are actually victims of a horrifying project. These kids are neither truly alive nor dead—they are the result of a bizarre scientific process designed to erase their memories and keep them in a state of perpetual growth, without a real origin or ending. The camp’s director, Collins, and the staff have been using this twisted procedure for years, turning the children into living experiments in a cycle of memory deletion and physical growth, which is why Morgan and the others find files indicating they have no real past or future.
In the film’s climax, Franklin confesses to Morgan and Pilar that the children, including Morgan himself, were once dead and have been subjected to a scientific manipulation to keep them in a limbo state. This revelation explains why the “doctor” appears with a stun baton—he is not a ghost but a rigged-together construct or a malfunctioning part of the experiment, designed to intimidate or control the children. The story suggests that the camp’s horrific practices are part of a larger, global pattern, as Collins later receives a call about similar cases worldwide, hinting at an extensive and ongoing experiment involving these child “creations.”
In the final scenes, as Morgan and Pilar face the reality of their situation, Franklin offers them a choice: to undergo the procedure and forget everything, or to refuse and retain their memories and self-awareness. It’s implied that most of the kids go through with the memory wipe, accepting their manufactured existence, but Morgan and Pilar decide to resist, choosing to remember who they are. The film ends with Morgan feeling a sense of hope and camaraderie with his friends, standing outside the camp and embracing their shared reality. Meanwhile, the authorities and the camp’s staff are left uncertain, with Collins receiving disturbing news about the global spread of similar cases, indicating that the horror of the experiment might not be over. In a chilling final twist, it’s suggested that the glitches and “monsters” are not bound by human morality—they could turn on anyone, including Collins himself, as revealed by the final encounter with a bloodied girl attacking him with a knife, leaving the story open-ended with the suggestion that the horror could continue indefinitely.
