The Zodiac Killer, a serial killer who operated in Northern California from the late 1960s to the early 1970s, is one of the most notorious criminals America has ever seen.

The Zodiac Killer’s crimes, letters, and cryptograms mailed to newspapers and the police have inspired television productions, novels, and motion pictures. A feature film starring Robert Downey Jr. and Jake Gyllenhaal was made about the man whose identity remains unknown to this day.

New DNA technology is a glimmer of hope for California detectives, desperate to solve the 50-year-old mystery. According to United Press International, detectives are hoping to take advantage of the same DNA technology used to capture the alleged Golden State Killer.

After four decades, a man believed to be the Golden State Killer was arrested on charges of killing eight people. Joseph James DeAngelo, now a 72-year-old former police officer, tormented California residents between 1976 and 1986. DeAngelo, police said, committed at least 12 homicides, 45 rapes, and dozens of burglaries across California.

New DNA technology was credited for cracking the decade-old case. The detectives used a public database of genetic genealogy called GEDmatch – they created a fake profile and uploaded a real DNA sample. After finding matches from distant family members and going through the Sisyphean process of reconstructing family trees, detectives were led to the door of the killer, Joseph James DeAngelo, the Conversation reported.

Law enforcement officials in Vallejo, California, and San Francisco and Napa counties are re-evaluating potential DNA evidence left behind by the Zodiac Killer. They believe genealogy databases, like GEDmatch, will lead them to the Zodiac Killer. Potential Zodiac Killer DNA will be tested against an expanded pool of samples used in genealogy research.

“If we get a good profile, then you start tracking back. It really comes down to DNA. Without it, you have nothing. It’s a 50-years-old case,” Vallejo Police Detective Terry Poyser said. His team has resubmitted two envelopes to a lab. Detective Poyser believes he’ll have the results of the testing within weeks, at which point his team will test the DNA against a pool of samples used in genealogy research.

Most investigators believe the Zodiac Killer is dead. The killer sent his last verified letter in 1974, a few years after his final murder. Vallejo police say they’re encouraged by the new possibilities and hope DNA will lead them to whoever the Zodiac Killer was, or is.