Six years ago, I read Gary L. Stewart's book The Most Dangerous Animal of All as soon as it hit bookshelves. I remember the publisher had kept it under wraps, as the book offered a promising new theory regarding the identity of the Zodiac Killer. I read it with great interest, but I never saw it as one of the titans of the true crime genre due to its ambiguity. A four-part documentary series based on the book premieres on FX on Friday night (and is available on FX on Hulu the next day), and it boasts some …

FX has released a trailer for The Most Dangerous Animal of All, the network's first true-crime docu-series that dives into one man's possible shocking connection to history's most famous cold case. The four-part series is based on the book by Gary L. Stewart, whose search for the father he never knew led him to believe he might be the son of the notorious Zodiac killer. This is a...genuinely insane story, and almost impossible to believe in that way most true-crime seems impossible to believe. I mean, this FX series isn't about …