rpg

A modern day police procedural, likely using either CORPS (if I want crunch) or FATE (if I want drama). Think something like Law & Order without the fascist apologia (but WITH Jerry Orbach!) expanded a bit to include peripheral characters including the criminals, the families of both sides, etc.

And then the world ends.

Well, not quite ends, but there's a rather sudden drop in the standard of living as the half of the world facing the sun gets burned to a crisp, in effect, while the ensuing massive wave of fire and plasma scorches most of what is left. Only very small portions of the world survive (and that only barely). Nobody IC will know how or why it happened (I naturally will—it's one of the scenarios taken from CORPS Apocalypse) but when it does, the characters will have to face living in a world where most of humanity is dead, the trappings of civilization are gone (most important of those being the supply chains that keep cities alive!) and all that's left are the buildings and a rapidly-dwindling supply of essentials.

I tried doing this once when some players were saying they wanted a campaign that would surprise them. And surprise them it did, but apparently this was not the kind of surprise they were looking for. I want to try it again with players who will be strongly warned in advance that the campaign will go completely off the rails and change genre after a few sessions of play establishes their characters, their personalities, their relationships, etc.