A group of social media experts are hired to help an old family business to strive, by creating compelling stories about an old witch myth. But they soon find themselves stuck on a tiny island in a lake in which the ancient Swedish witch is said to live.

The film centers on Dr. Marcus, a renowned psychiatrist who has selected 6 severe mentally ill and dangerous patients from the Spring Valley Mental Hospital to interview as part of research for his new book. As Dr. Marcus interviews each patient, one by one the horrors they have committed begin to unfold. However, Dr. Marcus soon learns that there is one patient who ties them all together - Patient Seven.