Astrepius shakes the proffered hand, then in a phlemy voice the old sage answers, "Nobody? I'm not sure what you are referring to, but I am the sage that has employed these three gentlemen to help in a matter of potentially dire import. I'm not sure that the idol is in the sewers, though recent events point in that direction. The idol was in the possession of a shifter of my acquaintance. I've seen it once, but he was going to share his discovery with me so that I might study it further. Unfortunately he was murdered. The idol has gone missing. I do not know for certain what the idol represents but my research indicates that it is central in the worship of an ancient malevolent being and tied to dark practices of pre-Imperial times."
The sage pauses as a cough interrupts him as he clears his throat before continuing, "It was recovered originally from a cult that was sacrificing to the idol in the sewers and it would appear that a new gang called the Shards have moved into the sewers. That gang was attempting to stop my friends here from searching the shifter's residence for clues. It is my belief that the gang is in possession of the idol now and are in the same location that it was originally retrieved. So yes a trip into the sewers is in order, though I doubt that rats will be your biggest worry."
EDIT: ooc: rereading the whole thread I had to correct a minor point about the idol. I've highlighted the change.