Author Jarett Kobek believes he’s uncovered the true identity of the Zodiac Killer: an eccentric man named Paul Doerr, who died in 2007. Doerr’s daughter, Gloria, isn’t so sure — until Aaron Gell suggests that the two of them come together to meet. In this chilling story for Los Angeles magazine, Gell describes how Kobek’s research led him to Doerr, and how the evidence against Doerr is strong, especially after conversations with Gloria about her father, her childhood, and their relationship. But is Kobek just another amateur sleuth claiming he’s cracked the case?

As Jarett is quick to point out, the timing of the incident seems important. Gloria was only allowed to date on Friday nights, and she remembered this life-changing moment occurring at the beginning of Christmas break. Assuming her memory is accurate more than 50 years later, a quick glance at the 1968 calendar narrows down the date to one possibility: December 20. “You know why that’s interesting?” Kobek asks. It dawns on me slowly, although every halfway decent Zodiac researcher will likely know the answer: It was the night the killer claimed his first victims.

Indeed, the first three attacks took place at teen hangouts, places that, as Paul well knew, Gloria herself frequented, either on dates, as with the makeout spots at Lake Herman Road and Blue Rock Springs Park, or when cutting school with friends to swim at Lake Berryessa. Moreover, they were all places, Gloria confirms, where drugs could be procured.

Whether or not Paul Doerr crossed the line from domestic abuser to murderer that night, it’s easy enough to imagine him out looking for her, a tormented parent in search of his unruly daughter.

Cheri Lucas Rowlands

Cheri has been an editor at Longreads since 2014. She's currently based in the San Francisco Bay Area.