Kelpie is about fourteen or fifteen and only remembers a gypsy life traveling with Mina and Bogle. They use her to steal and read the crystal, for she has second sight. Mina keeps promising to teach her witchcraft without actually showing her any. Still, they are often accused of being witches and hounded out of town.
Then one day she pretends to fall in front of a party of young men only to find she has actually injured herself. Although they catch her stealing from them, they are amused by her and take her home with them. The young men are Ian, Cameron, and Alex, returning from Oxford to their home north of Inverlochy.
Kelpie stays at Glenfern with Ian’s family, eventually as a servant, but they treat her kindly. She begins to feel affection for the children, especially little Mairie, and is dismayed when Mina and Bogle reappear. Mina threatens to curse the family if Kelpie refuses to come with them, and since Kelpie believes in Mina’s power, she goes.
The Highlands are in turmoil because Argyll has been commissioned to secure the area for the Calvinist Covenant against King Charles. Argyll’s troops are more prone to burn villages and murder innocents than to fight armies. But Montrose is trying to raise men to fight for the king. Mina sends Kelpie on a perilous task, to steal some hair or a personal possession from Argyll so he can be hexed.
Kelpie’s adventures take her all over the Highlands. When she joins the followers of Montrose’s army, she is happy to meet Ian and Alex again, but she has seen Alex strike Ian down in the crystal, so she is wary of him.
This is an enjoyable novel for tweens and teens full of likable characters and nasty villains, some history, lots of adventure, and another feisty Watson heroine. Kelpie begins re-evaluating her moral choices through the examples of others and the kindnesses she receives during her travels.