The Shadow has a long and storied history. Over the course of the character's radio and publishing history, The Shadow became an American icon in his own right, and was even the inspiration for Batman, V for Vendetta, as well as being cited as a strong influence on the evolution of comic book heroes in general.
The Shadow has many ties to DC, even though the character was published by many different companies at different points in history. Superman co-creator Jerry Siegel, and Lester Dent (who wrote the Doc Savage stories) both wrote stories for The Shadow, among others.
DC Comics first published a Shadow series in the mid 1970's. An aging Shadow also appeared in Batman comics in which it is revealed that (in-universe) The Shadow was Batman's "biggest inspiration", as well as the surprising facts that The Shadow saved a young Bruce Wayne as a boy, and that The Shadow knows who Batman is, but the secret is safe with him. Batman also referenced The Shadow when he was once disguised as a night janitor at a police station, a method which The Shadow often used to obtain access to police records in his day.
Another couple of DC published Shadow series was released in the 80's, and there was one more in the 90's. The Shadow also made a few cameo's in other comics in the 90's.
This fanfic blends the radio version with the novel and comic book version. Certain RPG systems have been used to provide stats for the character to make tracking of changes easier. This interlude does not cover the many other Shadow comics, novels, pulps, and even movies that have been published over the years.