Phyllida is one of seven sisters to attend Queen Anne's School, where they are known as the "long family of Shortt," responsible for a list of escapades to their credit and discredit. During the summer holiday, Phyllida tries to rescue a swan being hurt by a spoiled girl called Queenie, soon to be a student at Queen Anne's. The rescue mission ends badly, with Phyllida bitten by a dog and Queenie pushed into a river. However, the holidays conclude happily with the wedding of the eldest Shortt girl, Pam.
Back at school, Phyllida likes beginnings so enjoys the first few days in the third form, and is delighted to see old friends and enemies. Naturally, the annoying Queenie turns up in her form, accompanied by a shabby and shy girl Violet. Phyllida's initial dislike of Queenie is renewed but her sympathy is awakened by Violet's discomfort. Will new girl Queenie ruin the term for Phyllida?