The man suspected in at least 50 rapes and 10 homicides throughout California whispered a message on a surviving victim's answering machine.
"I could kill you," he said after several heavy breaths. "I could kill you."
The prolific serial killer and rapist appears to have been dormant since 1986, but authorities still don't know his name or his face. Still, investigators are holding out hope that they will find him.
He has been dubbed "The Original Night Stalker" because his crimes predate those of the "Night Stalker," convicted serial killer Richard Ramirez, who died of cancer in June on Death Row.
Larry Pool, a retired investigator for the Orange County Sheriff's Department, tried to find the Original Night Stalker for 16 years before he retired.
"It sticks with you," he said. "It's a case where you don't want to breathe your last before we see the offender identified."
In the "Original Night Stalker" cases, authorities have the recording, handwriting samples, a footprint and a huge amount of DNA evidence that links at least 10 murders and 50 rapes to one man.
But they don't know who all of this belongs to.
His 10-year crime spree began in 1976, and the terror extended from Sacramento to Irvine. Two double-homicides were in Goleta, just north of Santa Barbara.
Detectives found shoe imprints and twine used to tie up his victim near a crime scene there.
Pool said the killer appeared to get around on a bicycle and target first-level homes and apartments near green belts.
In at least one case, police found a detailed, hand-drawn map of a neighborhood he terrorized in Goleta. On the back of the map was a single word: PUNISHMENT.
Some believe the killer is still alive, and could be in his 50s or 60s.