EXCLUSIVE: The rights to The New York Times bestselling book The Most Dangerous Animal of All, written by Gary L. Stewart who claims his father was the Zodiac Killer, is in final negotiations to be acquired by Ross Dinerstein and Campfire. First up will be a documentary with plans for a feature. The title of the book comes from the 1932 movie The Most Dangerous Game which law enforcement for years have said could have inspired the Zodiac killer.

There have been many theories over the years on who the Zodiac killer could have been. There have also been multiple movies made about the subject, including one directed by David Fincher, released in 2007, entitled Zodiac. That one was based on true crime author Robert Graysmith’s story while working at the San Francisco Chronicle when he attempted to decode the letters sent to the newspaper.

So what is Stewart’s story? He was abandoned in a Baton Rouge stairwell as an infant with only a dirty rag wrapped around him. Thirty nine years later, Gary (now 55), began his search for his biological parents, revealing a tumultuous affair filled with police records and newspaper articles outlining stories of statutory rape, disturbing connections to satanic cults, and domestic violence.

In May 2013, Gary was finally face-to-face with his biological mother. Three years later, Gary still had one question that had been gnawing at him since the day they met: Who was his father? This missing piece to his biological puzzle led Gary down a 12-year long journey that yielded a result no one would expect: the drawing of the face of the notorious Zodiac killer (as seen by the only victim the survived his attack) is eerily similar — actually almost identical — to the face of his father, Earl Van Best. Jr.

Van Best was also a known suspect in a case that has never been solved. The Zodiac killer claimed to have killed 37 people either by stabbing or shooting. Only one of the victims of the seven murders confirmed directly to the Zodiac killer would survive his attacks. However, there were questions about several others that were not conclusively linked to the serial killer.

Since there was only partial DNA and a partial print collected from the crime scenes, no one has been able to conclusively link anyone directly as the Zodiac killer. The SFPD still has that evidence.

Ross and Campfire are first making the documentary about the book, interviewing Stewart and co-author Susan Mustafa, about the evidence he compiled. So The Most Dangerous Animal of All is the next documentary following Unmasking a Killer to identify the Zodiac killer.

Helming the doc will be Kief Davidson who is an Academy Award-nominated director (Open Heart) and whose doc series have included The Ivory Game, Bending the Arc, A Lego Brickmuntary and The Devil’s Miner.

Ross’ other theatrical docs have included Jiro Dreams of Sushi, Silicon Cowboys, and The Nightmare.

Intellectual Property Group, BG Dilworth Agency negotiated on behalf of Gary Stewart and his co-writer Susan Mustafa along with WME on behalf of Dinerstein and Davidson.