An old map is found by a PC when he/she is on a trip aboard a fishing boat. The map has symbols written in an ancient language, one lost for hundreds of years, yet the PC becomes very curious to what the symbols may mean, if they have any meaning at all.
The PC takes the map to a mage that may hold the keys to the lost language, if it acctualy is one. Another PC hears about it from the shadowed alleys of the city, in which the PC carrying the map has asked for directions to where he might find such a person that could give meaning to the symbols. The new PC joins the party and helps take the map to an old friend of hi/hers which happens to be a mage that has the skill and tools necesary to fisure out what the map says.
The map shows the exact location of a ruined temple, where a gemstone was hidden. All this happened before the great wars that doomed the temple and the city beneath it. The gemstone used the energy that was found deep inside the earth to keep the gateway between the two worlds, that of chaos and the normal one, closed. When the great wars arrived, a scholar by the name of Kinuriel took the stone away from its rightfull place, in the chamber, and has taken it to the surface, away from the fighting that was going to take place underground.
When the wars were over, Kinuriel had survived, if barely, and had returned to Dreanor, the name of the underground city, to replace the gemstone and strengthen back the gateway. The stone could not find the energy it needed to sustain the portal at the surface, thus the gateway had beed weakening. Unfortunately, the wars had left him too weak to be able to venture back into the devastated city so he left the gemstone in a temple, built above the ancient city by the survivors so that it could hide the entrance to Draenor. He had also written a map, so that a stronger and braver warrior that himself might one day replace the stone.
The PCs must find this ancient temple and replace the stone into its rightfull place, on a pedestal, in a room, deep into the heart of the city.
Along the way, the PCs will fight the ancient horrors of the old city as well as the spirits of the fallen warriors that fought in the great war.