In a community center where a mass murder took place years earlier and it involves a paranormal investigator who discovers a door to another world.

In 1990, in a training center in Guisari, a building manager killed the guests and committed suicide. Since then, it became a place for suicides and there were also fatal accidents, so the training center closed and was abandoned. Many ghost stories are told about what they call 'Guimoon' a door where people enter, but do not come out of. Meanwhile, Do-jin, the director of the Psychic Research Institute, went to the training center to find out why his mother died while attempting a ritual; college students Hye-yeong, Tae-hoon and Won-jae, went to the center to record a video for a contest, were horrified facing a strange horror. If you can bear it, try to open 'Guimoon'.—Mahou 5 star