Agatha takes over the school, and without Mildred there, who will save the day?

As the end of year exams loom, Miss Cackle's secret is still weighing heavy on Mildred's mind.

Mildred learns about Cackle's history when she and Ethel accidently slip into the Cackle's of the past.

Amanda Holden flies into The Worst Witch playing head teacher Miss Pentangle, whose school is taking part in the Annual Spelling Bee against Cackle's Academy.

Everyone is excited, all except Miss Hardbroom, who balks at hearing the rival school will be visiting Cackle's and that Mildred is one of the contestants. Miss Hardbroom is doggedly determined that the school will perform brilliantly and puts a strict training plan in place.

Miss Pentangle and her contestants arrive, but why is Miss Hardbroom so on edge? Miss Pentangle is everything Miss Hardbroom isn't - colourful, cheerful and friendly... but could there be more to Ms Hardbroom's competitiveness than meets the eye?

Mildred goes on a hair-raising journey while looking into her magical heritage, meanwhile Ethel thinks she's queen bee when she grows a wart.

Maud's panic about parent's evening pushes her to use a forgetting powder, meanwhile Mildred wonders if her mum is a witch after all.

Mildred learns not to take short cuts when a wisdom spell goes wrong and she has to convince her class she's their new teacher.

Everyone is surprised to hear the Great Wizard is making an unexpected visit to Cackle's Academy. He has had a tip-off that the school is going rapidly downhill and it looks like non-magical Mildred is at the heart of the problems. Miss Cackle refuses to expel Mildred and waxes lyrical about her. The Great Wizard insists that Mildred should perform a magical display to prove herself. Creative Mildred conducts a magical potions choir, but it ends in disaster, leaving Miss Cackle on thin ice. With Miss Cackle not herself, and Ethel willing to do whatever it takes to get Mildred expelled, Mildred must somehow get to the bottom of things and prove to the Great Wizard that she deserves her place in the school.

Mildred makes a mistake which has unfortunate consequences for Ethel.

Everyone's excited at the arrival of Enid, a witch from the famous Nightshade family.

Mildred learns that having a scaredy cat makes life at witching school tough - especially when Ethel Hallow is determined to see her fail.

Second part of the premiere episode... Miss Cackle's evil twin-sister, Agatha, plots to become the new headmaster of the academy, but Mildred saves the day and exposes her. In her battle against her sister, Agatha's magic turns against her and leaves her magic-less. After saving everyone, Mildred is accepted to Cackle's Academy and Miss Cackle and Miss Hardbroom tell Mildred's mother about existence of magic.

Mildred Hubble's world changes when she learns about selection day at Cackle's Academy.