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.
Beneath the fake blood and cheap masks of countless haunted house attractions across the country, there are whispers of truly terrifying alternatives. Looking to find an authentic, blood-curdling good fright for Halloween, five friends set off on a road trip in an RV to track down these underground Haunts. Just when their search seems to reach a dead end, strange and disturbing things start happening and it becomes clear that the Haunt has come to them...