The Conclave have come to Marais, to destroy Swamp Thing once and for all.
Woodrue cuts into Swampy while Cassidy accepts his fate as the Blue Devil.
Lucilia settles the score with Avery. In the swamp, Abby and Alec run into danger.
Dr. Woodrue does an unsanctioned human experiment, while Dr. Arcane struggles to help Alec.
Dr. Arcane finds out more about the Green Flu as it spreads further and more dangerously through Marais.
Dr. Arcane meets Swamp Thing again, face to face. Avery is struggling to maintain control, financially and personally.
Abby tries to help Susie. So does Swamp Thing.
Dr. Abby Arcane returns to Louisiana to investigate an epidemic. She meets Alec Holland. Things get scary.