In this quest, you will have to defend the business interests of the rogue "D", from encroachment by the rogue "K". Your job is to make sure that "D" never has to worry about "K" again.
To complete this quest, you have to first kill "K"'s Lieutenant, then "K" himself.
To accomplish the first leg of this quest, start traveling around Denerim (Denerim Market District to The Pearl works nicely) and you will have an encounter at a Run-Down Alley with the Lieutenant and his henchmen. After a scuffle, he will be dead and after looting his body you should have a new location on your Denerim City Map.