The Treasure of Tardos

Dungeon Master sends the Young Ones to the walled city of Tardos Keep to save Queen Solinara and her people from Venger's besigement. But the evil wizard has a wicked surprise for the kids--Demodragon, a two-headed fire and ice spitting monster capable of trashing the entire Realm. Will they learn what the fabled treasure of Tardos Keep is before the out-of-control Demodragon destroys their chance to get home?