This adventure focuses on a Zhentarim attempt to spread terror in Mistledale, although it is suitable for almost any lightly settled area northwest of the Sea of Fallen Stars. "The Raiders of Galath's Roost" is suitable for four 1st-level characters, but PCs should be at least 2nd level before tackling the adventure's second half, the Zhentarim Citadel. Even in the first half of the adventure, many of the encounters are quite formidable for 1st-level characters, and the PCs might find it necessary to withdraw and recover one or more times before completely exploring the ruins.
The PCs follow the trail of some particularly competent kobold thieves to the lair of a dragon cult deep in the swamp. There they discover efforts underway to grant sentience to the skeleton of a powerful red dragon once named Flame. Eventually the PCs determine that trouble has returned to the Western Mountains in the form of a band of fire giants ruled by a clone of the original red dragon named Flame.