Somewhere, deep in the primordial forest known to men as Epping, lies a valley which time has forgotten and everyone else would like to. And in the depths of that valley, locked firmly into the solid granite is an iron grate. A grate which, if it could be opened, would lead the hopeful traveller into a vast network of underground caves in which he might find riches beyond his wildest dreams or encounter grim death in a thousand lurking forms.