A beautiful dress arrives at Malory Towers: one of the girls is a debutante, destined to marry into aristocracy. When Darrell finds out who the mystery girl is, she's determined to prove the girl is a poor choice.

Feeling guilty for lashing out at Mary-Lou, Darrell and Sally hatch a plan to give Mary-Lou the confidence she needs. But will the plan backfire and make Mary-Lou less courageous?

May-Lou is devastated to find her courage pen smashed on the floor. When Darrell's shoes are found with ink on them, Darrell is the prime suspect, and the North Tower holds a class court.

Darrell is up to play in the lacrosse game, but her excitement is short lived when she finds out they'll be playing against her old school. Darrell must face her past and overcome her temper if she wants to win the match.

After a confrontation with Darrell about her family, Sally is found hiding in pain. However, her injuries are far more serious than first thought. Fearing she is at fault, Darrell leaves the school to find a doctor.

Darrell is itching to get to the bottom of Sally's relationship with her family, but when Sally goes missing, the first form rallies together to comb the grounds. Darrell and Sally finally discover the real reason Sally was sent to Malory Towers.

In the dead of night Mary-Lou faints when she sees a hooded figure in the dorm bathroom. Not wanting Mary-Lou's courage to be crushed, Darrell and Sally are determined to get to the bottom of the mystery.

In awe of Malory Towers, Darrell keeps her past at her old school a close secret. Always in the thick of it, Darrell has a hairy start at the train station and when odd sounds are heard in the dorm, learns about the ghost of Lady Jane Malory.

On a scorching hot day at Malory Towers, Miss Potts lets the first-form girls go down to the pool. Jealous of Darrell and Alicia's new friendship, Gwen takes the fun and games too far.

On open day, Malory Towers bursts with energy and visiting families. But Darrell's joy is short-lived when she finds out her half-term results. She is determined to keep them a secret from her parents.

In an attempt to impress Alicia, Darrell unleashes a prank in Mam'zelle's class. Trick sweets sent by Alicia's brothers cause havoc in the school, and strange happenings continue when a mysterious red handprint appears in the dorm.

Alicia's family sends a bounty of food, and the girls are all set to have their first North Tower midnight feast. But when Matron wakes during the feast, all Darrell’s worst fears are realized. Will the girls escape?

When Gwen leaves the school to learn about Darrell’s past, Darrell must try to stop her before it's too late. Meanwhile, not knowing where their dormmates are, the North Tower girls do all they can to cover when the Matron comes for lights out.