1662. A dangerous time to be a woman, when even dancing can lead to accusations of witchcraft. When Sigri, desperate and grieving after the loss of her husband and son, embarks on an affair with the local merchant, it's not long before she is sent to the fortress at Vardø, to be tried and condemned as a witch.

Sigri's daughter Ingeborg sets off into the wilderness to try to bring her mother back home. Accompanying her on this quest is Maren - herself the daughter of a witch ­- whose wild nature and unconquerable spirit gives Ingeborg the courage to venture into the unknown, and to risk all she has to save her family.

Also captive in the fortress is Anna Rhodius, once the King of Denmark's mistress, who was sent in disgrace to the island of Vardø. What will she do - and who will she betray - to return to her privileged life at court?

These Witches of Vardø are stronger than even the King of Denmark. In an age weighted against them they refuse to be victims. They will have their justice. All they need do is show their power.