Jerry Hartfield is the producer of Grave Encounters, a reality television program directed by ghost hunter Lance Preston. Hartfield explains that the show was cancelled after five episodes following the disappearance of its crew, and presents raw scenes from recovered footage of the sixth and final episode. The Grave Encounters crew consists of Lance, occult specialist Sasha Parker, surveillance operator Matt White, cameraman T.C. Gibson, and fake medium Houston Grey. The crew is invited to examine the abandoned Collingwood Psychiatric Hospital, where unexplained phenomena have been reported for years. The hospital warden takes the crew on a day tour and informs them of the hospital's history, particularly of a doctor named Arthur Friedkin, who performed unethical experiments and lobotomies on the hospital's patients before being killed by them. The crew lock themselves inside the hospital for the night and begin their investigation, setting up camp near the main entrance. No paranormal activity seems to occur within the first few hours until a door slams behind T.C.. The crew attempts to establish contact with the entities, and the incidents soon become more hostile.
The crew begins to repack in preparation for the warden unlocking the hospital. Matt disappears and the other members spend several hours searching for him. When the warden does not return, the crew forces the front doors open but discover that they lead to another hallway, as well as to other false exits. They also note that it is still nighttime outside the building when their clocks indicate that it is well past morning. They encounter a girl whose face demonically distorts. As they flee in fear, Houston is strangled to death by an invisible force. The crew discovers that they have been fitted with hospital identification bracelets bearing their names. They find Matt, wearing a hospital gown and now insane; he mumbles nonsense and explains that the only means of escape is to be "cured" by the hospital's residents.
T.C. is pulled into a blood-filled bathtub and disappears while Matt throws himself down an elevator shaft. Lance and Sasha are attacked by a demon and enter the tunnels in search of an exit. Sasha falls ill and is abducted by a mist. The terrified and unstable Lance wanders the tunnels alone and feeds on live rats to survive. He finds a door leading into Friedkin's operating room, which contains evidence of satanic rituals and black magic. He sees the apparitions of Friedkin and several nurses, who drag the screaming Lance to an operating table. The camera cuts out for a few moments before it is turned back on by a lobotomized Lance, who proclaims that he is cured and allowed to leave.
Sean Rogerson as Lance Preston
Ashleigh Gryzko as Sasha Parker
Merwin Mondesir as T.C. Gibson
Mackenzie Gray as Houston Grey
Fred Keating as Gary Crawford
Juan Riedinger as Matt White
Arthur Corber as Dr. Arthur Friedkin
Bob Rathie as Kenny Sandavol (Caretaker)
Matthew K. McBride as Spiritual Force
Ben Wilkinson as Jerry Hartfield
Alex Timmer as The Tongueless Demon
Eva Gifford as Demon Girl
Michele Cummins as Bathtub Demon
Shawn Macdonald as Morgan Turner
Max Train as Punk Guy
Marita Eason as Punk Girl