A crystal key from another world? We should look into that. What could possibly go wrong?!

In studying a strange key made of metal and crystal, the Pathfinder Society has determined that it is receiving a distressing signal from a remote estate in mist-shrouded Ustalav. Other people in the area have been receiving the signal as well, but without the key, they have no way to interpret the strange messages and images. The Society must travel to Ustalav, investigate the source of the signal, and prevent the terrified populace from taking matters into their own hands!