From the back of the book:
The Secrets of Winter
Tear aside the veil and learn the sinister secrets of the Shadow Court. Discover their dark rites and forbidden Arts. But beware - the Unseelie do not take kindly to those who pry into their affairs.
The Shadow Court is a complete guide to the Unseelie for both players and Storytellers. This book offers a wealth of information - from playing Unseelie characters to running Unseelie chronicles. It offers everything from new Arts, kith and noble houses to secret societies, Unseelie festivals and customs.
The Shadow Court includes:
Three new Unseelie Houses of the sidhe.
New Arts for Unseelie characters.
A wealth of information on the history and culture of the Unseelie Court and the more sinister Shadow Court.