Thoughts

Okay, so cast list:

Sherlock Holmes: I'm still a RDJ fan, but I think that if you're looking for nerdier alternatives, Christian Bale, Hugo Weaving, and Michael Sheen would all make good choices. But my ultimate would be Michael Fassbender (Lt. Archie Hickox, Inglourious Basterds)
John Watson: I once heard you say that Jude Law was absolutely spot on as Watson, so he's my pick.
Mycroft Holmes: Stephen Fry. I don't even care who we cast as Holmes, but Stephen Fry is a fantastic actor, perfect for the part and has already been cast for the role in the RDJ-Holmes sequel.
Lestrade: Stephen Moyer, who plays vampire Bill Compton on True Blood, would make an awesome Lestrade. If you see him in interviews, he's a very British gentleman.
Mrs. Hudson: I kind of like Alliso Janney for this.
Roslyn Wickham: Freida Pinto, the love interest from Slumdog Millionaire. I'm still ironing out the details, but her father is a friend of Watson's from the army. He was stationed early in his career in India and had a baby with a local, so she's half-Indian.
Stanley Hopkins: I was browsing Wikipedia and he seemed like the best secondary Scotland Yard detective to bring in. I was thinking maybe Matthew Bomer from White Collar or Jesse Spencer from House.

I still think our biggest hurdle is going to be plotting. I know that with regards to our LotR collection, I said going on the fly would be best, but as we need to be able to write Holmes making his grand conclusions out of minute details, we need to be very exact with every detail of the crime before we go forward with the story so that we can plant the clues ourselves.

So far what I've gotten is:
-Involvement of a shady law firm called Wolfram and Hart
-Some sort of trip to an opium den
-I did like the Catholic priest angle, but I think that the possibility of molestation should be sort of a red herring that everyone but Holmes follows
-Involves a noble family with secrets (because I think a masquerade ball would be fun)
-A MERDER most foul. We just don't know who.
-Wrongdoing on the part of the British government, causing the abduction of Mycroft Holmes

So, um, there's the brainstorming. It's the cohesion we're having trouble with.

Character Casting?

We'll need someone for Holmes, someone for Watson, someone for Mycroft, someone for Lestrade, someone for Mrs. Hudson... and your made-up character, to start. Obviously we'll have more characters as we progress. Suggestions for any/all?