After learning that his father may have been the Zodiac killer, Gary brings The New York Times best-selling true crime author Susan Mustafa into the fold to help uncover more information about him. Over the next two years, they follow a dark trail filled with unexpected discoveries as Gary attempts to find some closure.

• Kief Davidson
• Ross M. Dinerstein
• Elisa Bonora

• Kyle deCamp
• Gary L. Stewart
• Jude Gilford