From the back of the book:
The slave markets of Katapesh may be an unsavory sort of business, but the trade metropolis’s enigmatic law enforcers have few qualms with the legal act of selling and buying flesh. Other factions, including the abolitionist Eagle Knights of Andoran, have their own opinions on the matter, however, and frequently send undercover agents into dangerous territory to break up slave rings.
When one such Eagle Knight goes missing while investigating an underground slave operation beneath the dilapidated Twilight Gate district, it’s up to the PCs to delve an abandoned (but hardly uninhabited) qanat beneath Katapesh and discover her dire fate. Yet not everything is as it seems in the dank slave caverns under Twilight Gate, and clues hint that the slavers may have even more loathsome connections than initially suspected. Can the PCs recover the missing Eagle Knight before her fate is sealed? Or will the monstrous slavers lairing under Katapesh succeed in their malevolent designs?
Broken Chains is an investigatory dungeon crawl adventure for 6th-level characters, written for the Pathfinder Roleplaying Game and compatible with the 3.5 edition of the world’s oldest RPG. This volume also contains a fully detailed map and gazetteer of the Garden of Chains—a nefarious slave auction house—and a brand-new demon that can easily be used in any campaign.