In the Inn in Crescent Reach, there's a sleeping NPC in one of the rooms. When hailed, he pops up and if you follow the quest [text], you arrive at a quest to rescue this guy.
The reward is Barrier of Black, a nice shield indeed. http://lucy.allakhazam.com/item.html?id=53694
Only speculation on my part, as I haven't progressed in this quest yet, but there's an Orc Keymaster or somesuch that probably needs to die at some point in this quest.
Edit: Next step is indeed to kill the Orc Keymaster.