Before the Brodie set turns sixteen, Miss Brodie tests her girls to discover which of them she can really trust, ultimately settling on Sandy as her confidante. Miss Brodie is obsessed with the notion that Rose, as the most beautiful of the Brodie set, should have an affair with Mr Lloyd in her place. She begins to neglect Mr Lowther, who ends up marrying Miss Lockhart, the science teacher. Another student, Joyce Emily, steps briefly into the picture, trying unsuccessfully to join the Brodie set. Miss Brodie takes her under her wing separately, encouraging her to run away to fight in the Spanish Civil War on the Nationalist side, which she does, only to be killed in an accident when the train she is travelling in is attacked.