For those who were alive in the '80s when "Poltergeist" first appeared on the big screen and scared fans all across the nation, the movie wasn't the only thing that had people shaking in their boots. The film and its sequels were heavily rumored to be cursed due to unexpected deaths by the first film's youngest stars.

First of all, you need to take a look at the first film to put this supernatural theory into perspective, according to Movie Pilot.

The young actresses Dominique Dunne and Heather O'Rourke both played the two daughters of Steven and Diane Freeling (played by Craig T. Nelson and JoBeth Williams) in the film. The family was living in a house and they were digging a swimming pool in the backyard.

The film centered around Carol Anne (O'Rourke), the child who the dead were communicating with. The demon, or "The Beast," eventually kidnaps her through a portal in her closet but they eventually get her back.

There is also a scene were Diane had slipped, during a thunderstorm, into the giant hole meant to house the impending swimming pool. As she struggles to get out, dead corpses surface along with coffins. It is later revealed in the movie that their house had been built on top of an improperly relocated cemetery.

This is where the curse starts taking shape. The two young actresses, Dunne and O'Rourke, would eventually die under mysterious circumstances.

On Nov. 4, 1982, Dunne died following a strangulation incident that occurred four days earlier on Halloween while rehearsing lines with a friend for an upcoming movie. Dunne's estranged live-in boyfriend showed up and after a fight, the argument led to him strangling her. Dunne lived for four days after the incident in a coma before she finally passed away.

According to Snopes, her boyfriend, John Sweeney, was charged, convicted and sentenced to six years in prison for her murder, but only served three years before his controversial release.

O'Rourke went on to film two more "Poltergeist" movies but shortly after wrapping the third film, she died of cardiac arrest following a misdiagnosed case of stenosis. She died on the operating table while surgeons were trying to repair the damage on Feb. 1, 1988.

According to a BuzzFeed video, O'Rourke's brother in the first film had a poster on his wall of Superbowl XXII, which was still six years away. Coincidentally, O'Rourke died the day after the actual Superbowl XXII.

The curse thickens though when actors Julian Beck and Will Sampson joined the second movie, according to another article on Movie Pilot. Beck played "Kane," who turned out to be the materialization of the "Beast" from the first film, which we never saw the character in. Sampson played the Native American Medicine Man named Taylor.

Both died of health-related complications following the movie's release. Beck died of stomach cancer in 1985 and Sampson died of kidney failure in 1987 following an operation that was brought on by preoperative malnutrition issues.

Lou Perryman, the man who played Pugsley in the first "Poltergeist" film, was murdered with an axe at his home in 2009.

This string of violent and unexpected deaths led to many calling the film franchise cursed. But the real kicker is what the producer Steven Spielberg used in the first film as props.

Do you remember that scene previously mentioned about Diane slipping into the giant muddy hole during a thunderstorm and grappling with dead bodies that revealed the remains of a cemetery? Those bodies . . . they were REAL human bodies. Apparently, it was cheaper to use these real corpses, which were flown in from India, than to make fake ones.

Will Sampson even performed an exorcism on set, while shooting the sequel, to rid them of evil spirits.

See video about the curse below.