The Swamp Thing character first appeared in House of Secrets #92 (June–July 1971). 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. InSwamp 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.