Kalainen is a distrusted outsider in the port of Shaddimur, solving crimes that baffle the City Watch. Joining his team of Imber, a cunning rogue, and Mardenifol, the unwanted third son of a noble with a troubling enthusiasm for chemistry, is Faro, a large woman from a disbanded regiment just trying to do her best for her family. Carrying a pack of strange glassware, a lone traveller has been murdered outside Shaddimur. And then the much-needed lighthouse on Crab Island has gone dark. What has happened to the lightkeepers, the repair crew and even the military detachment sent to the mystery island? Surely it is in nobody's interest to damage the light? Another baffling case for Kalainen, the Drouhin of Shaddimur.