When the kindly old lord dies mysteriously and his nephew Lord Antonio occupies the castle high on the hill, the peasant folk in the village below begin to fear him. There are rumours of strange practices and ceremonies, far removed from their Christian beliefs.
Once the soldiers come to collect their young, unmarried women to take part in these secret rites, the villagers are terrified, especially as some of the girls never come home.
Catrin is full of dread when it is her turn; however, she has a secret. Rather than being a maid, she and her swain Elis have plighted her troth and she suspects, to her joy, that she may be expecting their child.
This makes her all the more determined to survive her ordeal in the fortress, whatever that might bring, even if it means she has to resort to witchcraft and enchantment. Might her pact with the devil lose her everything she holds dear?