Wow this is pretty exciting!!
Just a suggestion for Dan and Dave...
I do tech support for an online casting database that has locations in LA,NY,MIAMI, and SF.
Since I heard the project was greenlighted for a pilot I've been sort of amusing myself doing searches of the database for actors that meet the description of various characters in the book.
I realize you guys will be doing most of the shooting in the UK and may wish to do most of your casting for actors in that region, but maybe you would find the site a useful resource.
Anyway the site is called castingnetworks.com. It's a closed database that only provides access to professional casting directors. I don't want to bore everyone on the forum with details but if you think using the site would be helpful I can provide them if you guys are interested.
Either way good luck with the casting, and thanks for taking the input of the boards into account, it really means alot to those of us who love these books so much!
