You never really know what you might stumble upon while you’re tidying up the office. For DC Entertainment Co-Publisher Dan DiDio, it wasn’t some long-forgotten treasure, but rather a rejection letter he received four decades ago from the very company he’s called home for the past 15 years.

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On Facebook, DiDio posted photos of both the DC submissions policy from the time, and the rejection letter he received on Oct. 17, 1977, accompanied by the following caption:

This morning’s oddities while cleaning. Came across my first DC Submissions Policy and subsequent reject letters, the pitch, I believe, was a team book featuring The Creeper, Black Orchid and Code Name: Assassin, called The Outsiders. Fan fiction at its worst, but I still like the name.

This morning's oddities while cleaning. Came across my first DC Submissions Policy and subsequent reject letters, the…

Posted by Dan DiDio on Saturday, September 16, 2017

DiDio joined DC in January 2002 as vice president-editorial before being promoted two years later to executive editor. However, the biggest change came in February 2010, when DC Entertainment President Diane Nelson named him and Jim Lee as co-publishers.

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DiDio and Justin Jordan will co-write Sideways, a series that will spin out of Dark Nights: Metal as a part of DC’s new Dark Matter line.