The Purloined Rapier

From the introduction:

Our renowned party of seasoned adventurers, known as the Fixers for their reputation of resolving problems of folk all across the Feywood, have decided to do a bit of purposeful shopping in the City of Karnstown. They are seeking out a highly skilled weaponsmith capable of etching their weapons with runes of power. But before the shopkeeper can help them, the party must help the shopkeeper avoid a situation. Otherwise, the shop shut down, the weaponsmith's reputation ruined at best, and his life forfeit at worst!