The main series characters are introduced. Swamp Thing first meets 11-year-old Jim Kipp whose divorced mother, Tressa, is visiting her mother’s home. Jim encounters Humphrey, a dwarf who has escaped from the evil Dr. Arcane. Tressa struggles with raising her son as well as finding her magic powered necklace, called “the emerald heart” in the swamps.
Jim and Oboe sneak out on a midnight visit to the swamp and are resolute to see a mystical spirit called the Swamp Maiden who appears only once every three years. Jim plans to take pictures of her although both have been warned not to touch her. An unknown man offers to buy the pictures that Jim might take.
Arcane's protégé, named Crown Prince, is experimenting with hatred pheromones and his latest batch is released into the swamp air and Tressa is infected with the chemical agent which leads to all townspeople that she comes into contact with wanting to kill her. Only an intervention from Swamp Thing as well as Jim can cure her.
Swamp Thing is overcome by toxic waste and falls unconscious where he is found by two clean up men and is sold to a carnival freak show ran by a cruel man in league with Arcane. Jim stumbles by and sees the weakened Swamp Thing in a cage, and he is its only hope to get him back to the swamp to recover.
Swamp Thing is teaching Jim about endangered planets in the swamp when they come upon an area Swamp Thing refused to explain or let Jim go into that looks intriguing to a young boy's fancy. Jim being the inquisitive bash young boy he is, can't resist returning to have a look. During his brief visit he is bitten by a venomous insect created by Archane.
Jim and Tressa may have to leave the swamp after a lawyer delivers a notice of eviction. But they are unaware that the lawyer is in league with Dr. Arcane whom plans to use the property to expand his lab. Only through dreams does the late Tressa’s mother communicates to her with clues to find her real will guarded in the swamp.
Arcane captures Jim and sells him into slavery after the boy is witness to the evil doctor's hideous transformations of men into monsters and the local sheriff is in on the plans. Jim’s 17-year-old half-brother, Will, arrives to investigate Jim’s disappearance and teams up with Swamp Thing to find Arcane’s secret lab, but neither are aware that Jim is already gone from the country and the sheriff is one step head of their moves.
When Tressa accompanies her old college roommate, Ilene, and her daughter on an overnight camping trip, Arcane traps Ilene and her daughter behind an invisible force shield and only Swamp Thing can rescue them when Tress is disabled by a snake bite and both Will and Abigail are powerless to do anything.
Tressa accidentally stumbles across Arcane's latest model of two robot henchmen, called Watchers, who are hunting down Abigail to erase any evidence of the late Dr. Woodroe’s test tube experiments. Meanwhile, Will decides to throw Abigail a birthday party when she does not remember her birthday since she never had biological parents.
Will's estranged father shows up looking for a rare white orchid that Arcane and his henchman, Graham, has nefarious plans for. Tressa struggles with her romantic feelings for him, and Abigail, working in the town’s greenhouse, succumbs to the poisonous fumes of a certain red orchid, and only the healing powers of the white orchid can save her.
Under pressure from his superior, the shadowy General Sunderland, Arcane experiments with artificial earthquakes when he hires a hot female engineer, named Sienna, to create earthquakes at this latest weapon which leads to a personal conflict between Arcane and Sienna over the test runs, and it also lands Swamp Thing in a bind when he becomes trapped in the underground facility and weakening fast from lack of sunlight. Elsewhere, after Will goes out of town with Dr. Hollister to shop for a new truck, Abigail finds herself helpless when Tressa becomes pinned under the fishing pier during another aftershock and the rising river water threatens to drown her.
Tressa and Abigail are taken hostage by a man with a score to settle with Arcane, and whom has developed an environment destroying weapon called the Prometheus Parabola, capable of destroying the swamp and Swamp Thing intervenes in the literal shoot-out war at Tressa’s house to see that both sides do not activate the weapon while Will tries to rescue Tressa, Abigail, and Dr. Hollister from harms way.
Ian James is an unscrupulous anthropologist who releases poisonous tree frogs in the swamp to further promote his documentary film of the swamp while he charms his way into Tressa’s life while Will is as always suspicious to James’ true nature especially when James plans to catch on film the so-called Swamp Thing to further advance his career.
Ann Fisk returns to the swamp, intent on finding out if Swamp Thing is really the man, Alec Holland, whom she knew all those years ago and then tries to find a way to transform the creature back into the human scientist she once knew. But complications set in when two revenge-seeking redneck brothers take Ann as well as Arcane and his henchman, Graham, hostage and Swamp Thing is torn over using his powers to save them aware that his chance to become human again will be lost.
Arcane's genius mentor, Carl Mirador, has died. Using an experimental brain cell transfer, Arcane transfers all of Mirador's knowledge into his own brain. This does not go well as Mirador physically takes over Arcane’s mind and body. Meanwhile, Will meets and falls for Mirador’s granddaughter, Dana.