What's the premise for your game (or do your players haunt the forums looking for secrets)?
The game I'm considering running would be making use of the Block By Bloody Block supplement. I'm envisioning a game where some of the PCs are police and the rest are criminals. I'd start the game with an Assault On Precinct 13 type incident in which all the PCs are in the police station when it's attacked by "something". From here, I'd move to the PCs becoming full-fledged Hunters and starting to take back their city from the supernatural forces arrayed against them.
Some of the tricky things (and the solutions I'm playing with) would be:
Why do the cops and criminals work together? -- Well, they all get dumped into it together anyway. Also, I'm envisioning criminals with ties to a gang or organized crime, who also have a stake in protecting their turf. I'd need to emphasize to the characters playing criminals that certain types of characters are right out (no serial killers, sex offenders, etc.). Also, both character types would have something to bring to the table. The cop characters have the advantage of being able to play on their authority, to an extent, and to the resources given to them by the police department. Conversely, the criminal characters will have other, different resources, and won't be saddled by legal niceties that may restrict the cops.
How do the cops at one precinct manage to operate city-wide? -- I'm thinking that the cop PCs are all members of the "Special Investigation Unit", which is in reality a dumping ground for cops who have screwed up, offended the wrong higher-up, or are just a little off of normal. This lets me put their HQ in a run-down precinct, while still giving them license to operate city-wide. Also, this helps explain why they might be a bit more amenable to working with unsavoury criminal types towards "the greater good."
Anyway, those are just some initial musings ...
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