Superman just turned eighty years old. Batman will be hitting that next year. Many of the most popular characters in comics are well over fifty years old, including Spider-Man, The Hulk, Aquaman and many others. To say their backstories are convulted and difficult to figure out sometimes is an understatement. Not even a Wikipedia page can catalog their thousands of adventures.

For any writer coming in to writing a legacy character it can be daunting. How can you possibly catch up on that much material? What happens if you violate continuity in an issue from forty years ago?

For J.M. DeMatteis, a writer who’s worked on all the above characters along with dozens of others, it’s a constant challenge. When he first started working in comics he wanted to get every little detail right.

“If I got an assignment for Aquaman, I thought I had to go buy 500 back issues of Aquaman and read them,” DeMatteis says. “Although it was really just an excuse to buy more comics.”