From the title page:
At first it started as an occasional murmur, but soon the noise grew to a cacophony, like a thousand dwarves clanging their war cymbals over and over. The ringing stirred the drow into a frenzy, and all that is left are a few of you—misfits of the Underdark. To survive, you must band together and seek out alliances in a world of treason and deceit. Perhaps deeper down you can find the source of the madness and snuff it out, or tap into it for your own revenge. A heroic-tier D&D adventure with special monstrous characters provided.