Dennis Joseph O'Neil (May 3, 1939 – June 11, 2020) was an American comic book writer and editor, principally for Marvel Comics and DC Comics from the 1960s through the 1990s, and Group Editor for the Batman family of titles until his retirement. His best-known works include Green Lantern/Green Arrow and Batman with Neal Adams. For Batman, the team are credited with returning the Batman character to his dark gothic roots, in contrast to the campy Batman television series of the 1960s. However, comics historian Les Daniels considers O'Neil's "vengeful obsessive-compulsive" Batman to be an original interpretation that has influenced all subsequent portrayals of the character. It was during this run that O'Neil co-created the Batman villains Ra's al Ghul and Talia al Ghul. During their Green Lantern/Green Arrow run, O'Neil and Adams introduced a mature, realistic tone through stories such as "Snowbirds Don't Fly", in which Green Arrow's young ward Roy "Speedy" Harper is revealed to have become addicted to drugs. They also created and introduced the Green Lantern character John Stewart in 1971. As an editor, he is principally known for editing the various Batman titles beginning in 1986 after returning to DC. In 1989, O'Neil launched the Batman: Legends of the Dark Knight series, and was the writer for the "Shaman" and "Venom" stories. O'Neil led the Batman creative teams for the Batman: Knightfall (1993–1994) story arc. O'Neil co-created the antihero Azrael (Jean-Paul Valley) in 1992, who temporarily became the new Batman during Knightfall. After the storyline's conclusion, O'Neil was the writer for an Azrael monthly series that had 100 issues. His other notable work includes creating Richard Dragon with Jim Berry, and runs on The Shadow with Michael Kaluta and The Question with Denys Cowan. While working for Marvel, O'Neil scripted issues for The Amazing Spider-Man, Iron Man, and Daredevil during the 1980s. In the late 1990s, O'Neil taught a comics writing course at Manhattan's School of Visual Arts. He also sat on the board of directors of the charity The Hero Initiative and served on its Disbursement Committee. Early life O'Neil was born into an Irish Catholic household in St. Louis, Missouri on May 3, 1939. On Sunday afternoons he would accompany his father or his grandfather to the store for some light groceries and an occasional comic book. O'Neil graduated from Saint Louis University around the turn of the 1960s with a degree centered