Its a brutal crime from 1974 involving the torture (r*pe of one victim) and murder of three individuals at a home audio shop. Two people survived with life changing injuries. At one point the perpetrators forced all five victims to drink drain cleaner because it was recently portrayed in a movie as a quick way to kill somebody.
There’s a book (Victim by Gary Kinder) that follows one family through the murder of their mother/wife and their 16 yr old son/brothers fight for survival. I’d recommend giving it a read.