Darrell and her friends grow together as they share their schooldays. There are new students to induct, sporting matches to be won, tempers to control and tricks to play on teachers.

Games, lessons, quarrels and tricks all form part of a lively term, but the biggest event of all is the Fifth Form pantomime, written, acted and produced entirely by the girls. It generates a lot of fun, but also a surprising amount of trouble.

Darrell has left, and Felicity is head of the third form. And what a lot she has to deal with - June and new girl Freddie playing tricks continually, the sickly Bonnie shadowing her, and the stuck-up Amy, who has a strange family secret.

The girls return for another term to find several new faces in their form. There is Zerelda, the American girl, Bill, short for Wilhelmina, who is mad about horses, and Mavis who has a remarkable voice.

Susan is excited to be in charge of the winter concert, but Miss Tallant, a new teacher, has very strong ideas about it. And when she interferes in a midnight feast, they realise there's a spy in their midst. But who could it be?