(from the front cover) The small town of Welwyn has been beset by a string of robberies. The heroes are led to the natural cave system located at the bottom of the town well, which they must explore to find the burglars. But once they're in the cave system, things get much more difficult! The "burglars" turn out to be mere pawns in a much darker game. To get to the source of the crimes, the heroes must shrink themselves with potions of improved reduce person and explore a series of dangerous rat warrens where their prey is larger than they are!