Every writer has those set of characters that they just can't leave alone. That they go back to time and again because they're like a favorite set of children.
Typically I'd say this is most obvious in the way George Lucas writes about his Star Wars characters. The movies that are actually good Episodes 4-6 you'd say he found the heart of his story, place where all of the action happened. However, he can't stay away from them.
You got 1-3 mediocre film at best and now we're going to be getting 7-9. However, he always said he saw 9 films so who am I to judge. It's not like I don't have my own set of Star Wars characters that don't draw me back in from time to time.
However I think this stab at them just might propel me and my co-author into the mainstream. Missy and I refer to them as the girls. Honestly they've been kickin' around since 1997 and were the first thing we ever created together.
We cast it after the fact as far as the girls went and Kate Winslet became our guru. Maurice Benard has always been Beale Alstair and Stone had been a rotating character.