The crime
The murders of six members of the DeFeo family by a seventh, oldest son Ronald “Butch” DeFeo Jr. — and, perhaps, unindicted co-conspirators.

Possibly also the perpetration of a fraud on the public by George and Kathy Lutz, future owners of the DeFeo property, not to mention child endangerment; we’ll get into it.

The story
True crime and scripted horror activate many of the same nerve centers in the audience — that comparatively safe, controlled confrontation of visceral anxieties — so it’s not surprising that the Amityville case has become a preoccupation of a half century’s standing. That overlap isn’t entirely why it’s a preoccupation, but it’s relevant to our purposes here, to wit: what does MGM+’s Amityville: An Origin Story have to offer us as a true-crime property?