It was originally sposed to be about the Charlton characters DC bought, but then they switched it to a bunch of totally new characters, albeit just renamed & recostumed versions of the Charlton characters.
The whole basis of the concept was to present a more "real" superhero world. Sort of, what if our world had heroes?
There was some fantasy elements, but it was a lot more grounded than traditional DC/Marvel fare!
This book featured murder, homosexuality, middleage spread, insanity, rape & violence..............and thats just the heroes!