Poltergeist tells the story of the Freeling family, who move into a new home in California. Soon, they begin to experience strange and terrifying occurrences, which they soon discover are caused by malevolent spirits. The spirits, who are led by a vengeful entity known as "Bessie," begin to haunt the family, causing physical harm and psychological distress. The family turns to paranormal investigators for help, but they soon realize that the spirits are more powerful and malevolent than they ever could have imagined.