Spawned from a case first investigated by Ed and Lorraine Warren, the real-world paranormal investigators that the "Conjuring" universe is based on, the 1979 film "The Amityville Horror" would prove to be just the beginning of a completely unhinged pseudo-canon. That's because the "Amityville" universe is based on two things that cannot be trademarked even in the hyper-litigious world of U.S. intellectual property law — a real news story, and an actual location.

This means that, while there are a handful of Amityville films associated with that first Warner Bros. release, dozens of films have been made that bear the name. While all are to varying degrees connected to the 1977 novel about the allegedly haunted 1925 Dutch Colonial Long Island home where Ron DeFeo killed six family members in 1974, the big tent of Amityville movies includes a little bit of everything — a witch movie, a werewolf film, even a sexually explicit entry. As Michael Stone of Rotted Reviews put it, "I could fart on camera for an hour and a half and legally release it as 'Amityville Gas Chamber' and nobody would have any rights to sue me."

In a crime that has baffled criminologists and captured the imaginations of paranormal believers for decades, a then-23-year-old Ron "Butch" DeFeo Jr. shot his parents and four younger siblings, ranging in ages from nine to 18. Although author Ric Osuna would later point to the family's abusive patriarch and his alleged ties to organized crime as potential factors in the DeFeos' demise, supernatural claims from the home's future owners would eclipse any real tragedy in the public imagination.