Dennis J. O'Neil, also known as Denny O'Neil (May 3, 1939 – June 11, 2020) was an American comic book writer and editor. He worked for Marvel Comics and DC Comics from the 1960s through the 1990s. He was a Group Editor for the Batman family of titles until his retirement. O'Neil was born in St. Louis, Missouri.
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- Legendary Batman writer, Denny O'Neil dies at age 81