The sleepy village of Raven's Lake has a secret: A terrible god lives in the depths of the settlement's namesake. The citizens of Raven's Lake know that something lives in the lake. People who go out on the lake after dark go missing far too often and frequently turn up weeks later with no memory of where they've been. The local church of St. Cuthbert has been abandoned no fewer than seven times in the last two years, each time its lone cleric packing hastily and fleeing town without a word. Adventurers who come to Raven's Lake have a habit of vanishing forever. The truth is that something does indeed live in Raven's Lake but it is far from a deity. It's an exiled aboleth by the name of Zlorthishen.

This adventure is the ninth part of the Shackled City Adventure Path that began with "Life's Bazaar" (Dungeon #97) Wherein a group of diverse and talented allies learns the folly of not working together against a common foe.