The novel is set in Regency England somewhere around 1818, and events are related through third-person narrative. As the story opens, a wealthy, beautiful and intelligent woman named Annis Wychwood reaches the age of majority. Now having greater control over her personal and financial affairs, Annis decides to move to Bath and live alone, to the displeasure of her brother and his family. Several years later, on the way back to Bath after a visit to her childhood home, Annis meets Lucilla Carleton and Ninian Elmore. Lucilla is running away to Bath to avoid her marriage to Ninian, a match that her guardian is very much in favour of, and Ninian is escorting her to ensure her safe arrival. Annis volunteers to chaperone Lucilla and notifies the girl's guardian of her plans.