In the early part of the twelfth century in the northernmost reaches of Britain, Maya and her sister Alis live at peace on the Holy Isle of Eynhallow – until they are forced to flee from invading conquerors. They hide in the city of York until Maya is accused of witchcraft.

Child of Eynhallow mostly tells of Maya's beautiful and spirited granddaughter Isabel, who grows up as an outcast in her village and runs away before her father can sell her for twelve shillings. In this sweeping saga of courage and loyalty, Isabel confronts the brutal realities of medieval life, discovers her heritage, and finds love.