During the "Killer Clown" craze of 2016, Doctor Ellen Marks and journalist John Parker trace the source of the phenomenon to incarcerated, charismatic serial killer Carl Cane, who is using his sinister clown symbolism to recruit an army of the disenfranchised and launch a murderous anarchist movement across the globe. With Cane escaped and on the run on October 31 and Ellen's rebellious daughter in his thrall, can they stop him before he unleashes hell on earth on Halloween?