According to the adventure background provided, the plot involves the Blade of Fiery Might once wielded by the sultan of the efreet, which was destroyed and scattered across the planes.

Imperagon, a half-duergar/half-dragon and ruler of the Iron Fortress of Zandikar on the plane of Acheron, has been reforging the sword using the trapped spirits of the greatest forgemasters of history as slave labor.

The adventure begins when the player characters investigate events involving local craftsmen, following the trail of clues to the city of Rigus, which leads into the plane of Acheron.

Once there, the characters encounter formian settlers from Mechanus, whose hive can serve as a base of operations while preparing an assault on the Iron Fortress.

If successful in defeating the golems and steel predators that guard the fortress, the characters may breach its walls and destroy Imperagon's works.