One of the most prolific writers in comics, particularly in the Silver Age. He took over scripting duties on Wonder Woman after William Moulton Marston's death, and handled the character's transition from the Golden to the Silver Age. He also created Barry Allen, the second Flash, for editor Julius Schwartz's superhero revival of 1956, as well as writing and editing DC's pioneering war titles. His creations include Sgt. Rock, the Unknown Soldier, Barry Allen, Ragman, the Losers, Black Canary, the Metal Men, Poison Ivy, Enemy Ace, the Suicide Squad, and Rex the Wonder Dog.

Dennis "Denny" O'Neil was a comic book writer and editor best known for his work 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, The Shadow with Michael Kaluta and The Question with Denys Cowan. As an editor, he is principally known for editing the various Batman titles. From 2013 unti his death, he sat on the board of directors of the charity The Hero Initiative and served on its Disbursement Committee.