Miranda Brehault's free and happy childhood at Moondance, a crumbling old house on the edge of Dartmoor, comes to an abrupt end when she is left orphaned and penniless at the age of ten. Moondance's new owner, Theophilus Crowe, promises to take care of her, but instead he dispatches her to a cotton mill in Derbyshire.

Conditions at Crossbank Mill are harsh and pitiless; Miranda and the other pauper children are little more than prisoners. Desperate to escape, Miranda and her friend Biddie run away, helped by the mill master's young wife Caroline and by Caroline's rebellious cousin, Kit Warrener, who escorts the girls to Furze House on the south coast of Devon. As she grows to womanhood there amongst new friends, Miranda dreams of returning to Moondance, and of taking revenge on the man who ruined her childhood. Her growing attraction to Kit, who has become caught up in the smuggling trade, cannot distract her from her true goal. But will she choose revenge and Moondance over true love?