*Grins* This wasn't one of my NPC heavy concepts. or PC heavy either.
It is a bit epic, though.
The characters are rather experienced, beginning with base Arate 5, 15 Spheres instead of 6, and 100 EXP. The council member whom you represent as "justicar" will also entrust you with a combat related Wonder as a badge of office. (And I give a free dot in the Avatar background.)
The mission starts in Miami, (perhaps the home of some of the PCs, perhaps not, but either way they haven't been in Miami for a few months). One of the more powerful of the Cabals in Miami to survive the destruction of Doistep and associated devastation has disappeared and is believed destroyed. The mission is simply to investigate and terminate those responsible.
The reality is, of course, much more complicated.