In an anonymous location in Dolgellau is the headquarters of a secret agency that is investigating unexplained, supernatural events. As Beca and Ceri Fôn co-operate to try to solve the mystery, they are drawn into the entangled past of Wales, and learn that it's not from the outside only that danger lurks.

• Cover
• Clawr
• Teitl
• Hawlfraint
• Cyflwyniad a diolchiadau
• Prolog - Mis Medi, Aberystwyth
• Pennod 1 - Yma y Gorwedd ...
• Pennod 2 - Setlo'r Llwch
• Pennod 3 - Dadeni - 1939
• Epilog
• Drychwll, Siân Llywelyn