The documentary features interviews with several of Phyllis Seawater’s now adult children, including David, Don and Connie. “Mr. Allen” was the Seawater children’s teacher and their eventual father figure after he contacted their mother following their father’s internment at Atascadero State Hospital for molesting one of his daughters. Yep, this poor family went from being a father familias child molester to literally being the suspected Zodiac Killer (who was also a child molester for good measure).

This is the zodiac speaking contains many small details from the Seawaters’ adolescence that point to Allen’s guilt in the Zodiac. The Seawaters tell how Mr. Allen was an incredible swimmer who owned a black wetsuit similar to the clothing described in the Lake Berryessa murder. Connie even remembers sewing him a black hood. One of the Seawaters’ classmates, Darin Alvord, claims that Mr. Allen loved teaching his students all about alphabet codes and how to crack them.

More important than these small details, however, is the timeline that the Seawaters present. By the end of the three-part documentary, the Seawaters will have claimed that they were taken by Mr. Allen to every murder location, including Lake Herman, Blue Rock Springs and Berryessa, before the eventual murders. In addition, the Seawaters claim that they were taken by Allen to Riverside, California to attend a stock car race one day before the murder of Cheri Jo Bates on October 30, 1966, a murder that some investigators believe to be Zodiac’s first. In Episode 3 of the docuseries, David Seawater reports that an old and sickly Allen confessed to him during a phone call that he was Zodiac.

Most of Seawaters’ claims fall into the category of witness testimony, which is one of the least reliable forms of evidence – especially when told so long after the events. Still, the docuseries also offers some interesting bits of corroborating evidence for the Seawaters’ stories. The most striking new piece of evidence comes from one of the Zodiac’s many coded letters.

In 1973 the Albany Times Union The New York newspaper received a purported letter from the Zodiac, postmarked August 1. To this day it is unclear whether this is an authentic Zodiac correspondence or a copycat. A new detail makes a difference This is the zodiac speaking however, lends some credence to its accuracy. Connie Seawater’s daughter Tammie Lee Prueter remembers watching the History Channel special in 2017 The hunt for the zodiac killerin which producers had a supercomputer decode the encrypted portion of the Albany letter that would reveal the Zodiac’s next victim.

The computer allegedly decoded the victim’s name as ‘Connie Henly’, but they could find no meaning to it. However, both Connie Seawater and Tammie Lee Prueter report that the Phyllis Seawater’s maiden name was Hensley. Arthur Leigh Allen was one of the few people who knew that. Combine that with Zodiac’s penchant for intentional misspellings and the fact that Connie Seawater lived in Upstate New York in 1973, and it’s admittedly a compelling data point.