[Me of corse]

I can't find him I remember seeing a post on how to find the dwarfs son in the underdark but I have played through the game 3 times and never found him can anyone help I remember the post I read saying something about facits I assumed there were switches but have found nothing I think I know where he is north of the inn in the drow town but don't know how to release him. any help would be appreated thanks