Something unnatural is happening in the swamps outside Marais, Louisiana. When a mysterious illness strikes the town, CDC investigator Abby Arcane is sent to investigate. At the hospital, she encounters biologist Alec Holland who believes the bizarre illness might be connected to his scientific work in the swamp for powerful businessman Avery Sunderland. Along with Deputy Matt Cable, Abby and Alec encounter a terrifying, dark force that’s more than a swamp-born virus. Abby consults her old friend and local reporter Liz Tremayne who has a lead deep in the swamp. When Alec goes missing after investigating the unnatural experiments deep in the swamp, something else rises in his place: Swamp Thing, a mysterious creature born of the depths of the swamp’s mystical and terrifying secrets. With nature wildly out of balance and coming for the people of Marais, in the end, it may take some Thing from the swamp to save it.