In the annals of horrific Hollywood-related crimes that have left a lasting imprint on Los Angeles, the 1969 Tate-LaBianca murders have always ranked in the top tier. The bloody killing of pregnant actor Sharon Tate and others over two days by members of a cult headed by Charles Manson has sparked its own cottage industry of books and films, including Quentin Taratino’s “Once Upon A Time ..

. In Hollywood.’ But acclaimed novelist and former Times reporter Michael Connelly has always been fascinated by another dark and savage incident, fueled by sex and drugs, which he says left a deeper scar on Hollywood and L.

A. culture — the 1981 Wonderland Massacre, in which four people were brutally slain inside a posh home in Laurel Canyon. Adult film star John C.

Holmes, drug kingpin Eddie Nash , famed entertainer Liberace and his “boy toy” Scott Thorson were among the colorful personalities caught up in the case. A juror was bribed. Even after three trials, there were no convictions, and the killers were never brought to justice, making the Wonderland murders one of the LAPD’s most infamous cold cases.

The details, Connelly contends, were outrageous even by Hollywood standards: “There’s aspects of this story that I don’t think would work in fiction because you actually have to be more believable in fiction.” After decades of writing bestsellers — many of them featuring the fictional, no-nonsense Los Angeles Police Department Det. Hieronymus “Harry” Bosch — .