The village of Lonebridge is prosperous. The animals grow fat and healthy, the crops are abundant, and the people never seem to fall ill.
The villagers know they owe their good fortune to the brook that runs through Lonebridge and the spirits in the mountains from where the brook flows; they leave offerings at a small altar near the wellspring in the mountains. The finest handcrafted offerings will disappear from the altar. A delicate wreath of flowers or a finely carved wooden figure will disappear overnight when no one sees, but an expensively bought string of pearls will be left untouched.
But something changed three days ago. The water of the brook started tasting strangely metallic, a village elder fell ill and a young woman had a miscarriage. The villagers have been placing the finest gifts on the altar for the last three days, but none of the gifts have been accepted.
The village elders decided to send a group of young strong people to investigate and restore the brook and the village.