At 19, Conway began scripting
The Amazing Spider-Man, one of Marvel's flagship titles. His run, from issues #111-149 (Aug. 1972 - Oct. 1975), included the landmark
death of Gwen Stacy story in #121 (June 1973). Eight issues later, Conway and Andru introduced the Punisher as a conflicted
antagonist for Spider-Man. The character went on to become a popular star of numerous comic books and to be adapted into
two movies. Conway additionally scripted Marvel's other flagship,
Fantastic Four, from #133-152 (April 1973 - Nov. 1974)
Conway succeeded
Marv Wolfman as
editor-in-chief of Marvel Comics in mid-1976, but held the job only briefly, relinquishing the post before the year was out and succeeded in turn by
Archie Goodwin.
Conway returned to DC Comics in mid-1975, beginning with three books cover-dated Nov. 1975:
Hercules Unbound #1,
Kong the Untamed #3, and
Swamp Thing #19. Shortly afterward, he was chosen by Marvel and DC editors to script the historic intercompany crossover
Superman vs. the Amazing Spider-Man #1, a 96-page,
tabloid-sized, $2 one-shot, at a time when comic books sold for 25 cents.
He continued writing for DC, on titles including
Superman,
Detective Comics (starring
Batman), Metal Men,
Justice League of America, and that of the licensed character
Tarzan, yet briefly returned to Marvel as editor in mid-1976. For a time, a confluence of publishing schedules resulted in Conway stories appearing in both Marvel and DC comics in the same month: The prolific Conway's comic books with January 1977 cover-dates alone, for example, are Marvel's
The Avengers,
The Defenders,
Captain Marvel,
Iron Man,
The Spectacular Spider-Man and the premiere issues of
Ms. Marvel and
Logan's Run, and DC's flagships
Superman and
Action Comics (starring Superman).
After leaving Marvel's editorship, he again wrote exclusively for DC, writing both major and lesser titles — from those featurng Superman, Batman,
Wonder Woman, and the
Legion of Super-Heroes to such books as
Weird Western Tales,
Atari Force and
Sun Devils — through mid-1986. His co-creation Firestorm, "the nuclear man", debuted in the eponymous
Firestorm #1 (March 1978), which lasted five issues before being canceled during a 1978 DC retrenchment. The character then starred in a backup feature in
The Flash before again receiving his own series,
The Fury of Firestorm (later
Firestorm the Nuclear Man), from June 1982 - Aug. 1990; Conway wrote most of the first half of the run, plus four of its five annuals.
Conway returned to Marvel in the 1980s and served as the regular writer of both
The Spectacular Spider-Man and
Web of Spider-Man from 1988 until 1990. He relinquished writing duties on both titles when he became the script-editor of TV's
Father Dowling Mysteries.
Conway's last recorded comics credit is
Topps Comics' "Kirbyverse" one-shot
NightGlider #1 (April 1993), scripting from a Roy Thomas plot.