The Pathfinder Society has determined that a strange key made of metal and crystal is receiving a distressing signal from a remote estate. The Society must investigate the source of the signal and prevent the terrified populace from taking matters into their own hands!

This adventure is the first part of the two-part Crystal Key story arc. This arc concludes in PFS 4-11: Prisoners of the Electric Castle.

This adventure is a high-level adventure; no pregenerated characters are available. Experienced players must bring a valid 7th-10th level character.

Pathfinder Society is a worldwide fantasy roleplaying campaign using the Pathfinder Second Edition ruleset. Take on the role of an agent of the Pathfinder Society, a legendary league of explorers, archaeologists, and adventurers dedicated to discovering and chronicling the greatest mysteries and wonders of an ancient world.