La Créature du marais ou La Créature des marais (« Swamp Thing » en VO) est le personnage principal de la série de bande dessinée américaine du même nom créée par Len Wein et Berni Wrightson.

Elle connaîtra un renouveau grâce à Alan Moore, qui signera une œuvre définitive du futur label Vertigo de DC Comics où la série continuera.

Biographie

The Swamp Thing character first appeared in House of Secrets #92 (June–July 1971), under the name Alex Olsen. The comic is set in the early 20th century, when Olsen, a scientist, is caught in a lab explosion caused by his co-worker, Damian Ridge, who intended to kill him to gain the hand of Olsen's wife Linda. Olsen is physically altered by chemicals and the forces within the swamp. He is transformed into a monstrous creature who kills Ridge before the latter can murder Linda, who has started to suspect Ridge of murdering Alex. Unable to make Linda realize his true identity, he returns to the swamp.

After the success of the short story in the House of Secrets comic, the original creators were asked to write an ongoing series, depicting a more heroic, more contemporary creature. In Swamp Thing #1 (October–November 1972) Wein and Wrightson updated the time frame to the 1970s and featured a new version character: Alec Holland, a scientist working in the Louisiana swamps on a secret bio-restorative formula "that can make forests out of deserts". Holland is killed by a bomb planted by agents of the mysterious Mr. E (Nathan Ellery), who wants the formula. Splashed with burning chemicals in the massive fire, Holland runs from the lab and falls into the muck-filled swamp, after which a creature resembling a humanoid plant appears. Roy Thomas and Gerry Conway, who co-created Man-Thing for Marvel Comics a year and a half earlier, thought that this origin was too similar to that of their character, and Wein himself had written a Man-Thing story that was published with a June 1972 cover date, but he refused to change the origin in spite of some cajoling by Conway, who was his roommate at the time. Marvel, however, never took the issue to court, realizing the similarity of both characters to The Heap.

The creature, called Swamp Thing, was originally conceived as Alec Holland mutating into a vegetable-like creature, a "muck-encrusted mockery of a man". However, under writer Alan Moore, Swamp Thing was reinvented as an elemental entity created upon the death of Alec Holland, having somehow absorbed Holland's memory and personality into itself. He is described as "a plant that thought it was Alec Holland, a plant that was trying its level best to be Alec Holland" with the result that he suffered a temporary identity crisis as he tried to surrender to his plant side. Then he discovered that he could never be human 'again', but he eventually adjusted to his role after a fight with the Floronic Man. This new twist on his identity diverged the character from Marvel's character. This was Alan Moore's second re-invention of a comic book character, the first being Miracleman.

The major difference between the first and second Swamp Thing is that the latter appears more muscular than shambling, and possesses the power of speech. Being able to speak only with great difficulty, Alex Olsen's speech impediment is a major reason why his wife could not recognize him. In Swamp Thing #33, Alan Moore attempted to reconcile the two versions of Swamp Thing with the revelation that there have been many previous incarnations of Swamp Thing prior to the death and "rebirth" of the Alec Holland incarnation. Three others are notable: Albert Höllerer, a World War II pilot, appeared briefly and had his story summarized in Swamp Thing #47 (May 1986), and Aaron Hayley appeared in the Swamp Thing: Roots graphic novel (1998) set in the 1940s, and Alan Hallman, the Swamp Thing of the 1950s and 1960s, was introduced in Vol. 2 #102 (December 1990) and eventually, after being corrupted by the Gray, was killed by Holland. As a result, Holland is known as Swamp Thing IV by the editors of the DCU Guide. The principal two Swamp Things are also connected in that Holland's first wife is Linda Ridge, a descendant of Damian Ridge.