So how does this work? Are you given a story, with characters, and a basic plot, and then you sort of fill it out with the dialogue, or do you do story creation as well?

No, we write the stories as well.  

So, like, Avengers Assemble?  I got an email saying I was invited to pitch on the series. I had a phone call with Tom where I got the basics of the feel they were wanting for the book (rotating roster, relatively short story arcs) and I had a few days to put together my pitch.  

I wrote a paragraph on tone and themes, I think, then gave three sample arcs.  

Two of the three you’ve already read if you’re following the series.  

When you first start working with a company, you’re usually asked to turn in story outlines first.  Once they’re comfortable with your style, they’ll generally let you skip that step — as long as they know and have approved the basics of where you intend to go.  (This isn’t as Big Brother as people try to make it seem — editors need to co-ordinate for continuity, which is an impossible task under the best of circumstances.  If you’re going to do something to change the status quo of a character, they really, really need to know as far in advance as possible.) 

The writer then composes what is basically a letter to the penciller in the form of a script, describing the story… 

And so on. 

Does that help?