Deep in Florida's darkest everglades, a brilliant scientist, Dr. Alec Holland (Ray Wise), and a sexy government agent, Alice Cable (Adrienne Barbeau), have developed a secret formula that could end world hunger and change civilization forever. Little do they know, however, that their arch nemesis, Arcane (Louis Jourdan), is plotting to steal the serum for his own selfish schemes. Looting the lab and kidnapping Cable, Arcane douses Holland with the chemicals and leaves him for dead in the swamp. Mutated by his own formula, Holland becomes "Swamp Thing" - a half human/half plant superhero who will stop at nothing to rescue the beautiful Cable and defeat the evil Arcane...even if it costs him his life!