FX has just dropped the trailer for a new docuseries investigating the Zodiac Killer.
In the docuseries, Gary L. Stewart, a man who went on a quest to track down his biological father, claims that he has discovered the killer's true identity and has compelling evidence to back up his claim that it's his biological father, Earl Van Best, Jr.
Watch the trailer for The Most Dangerous Animal Of All below:Now, in case you're unfamiliar with the case, it's one of the most famous whodunits in American history, and theories have been circulating for decades about the identity of the serial killer who repeatedly struck in Northern California from the late 60s until the early 70s.
Per Bustle, five official murders have been linked to the killer, but the person responsible claimed to have killed at least 37 during their spree.
The killer gained notoriety for their calling card which detailed the specifics of their crimes and was signed off with the zodiac symbol, NBC News reports.
However, some of the notes were even more bizarre and contained cryptograms and ciphers, per a website dedicated to the killer, and they were allegedly the killer's way of hinting as to their true identity which, to this day, remains a mystery.

The show's official synopsis describes it as "an honest depiction of true life and true crime unexpectedly merging to upend one man's understanding of his own identity."
In the trailer, Stewart explains that he saw his father's name in one of the Zodiac Killer's ciphers, with the two men being proven to have near-identical handwriting. They also have the same fingerprint scar, which, per Bustle, means that there's a 99 percent probability that their DNA will match.
However, this is just a small part of Stewart's research, which he spent a total of 12 years collecting, and it's further substantiated by the fact that Earl Van Best, Jr. is one of three men who have dominated existing theories about who the Zodiac Killer might be, per BuzzFeed.