In The Worst Witch, although inadvertently ruining a broomstick display while she was lead, as she was given a sabotaged broomstick, she saves the whole academy from Miss Cackle's jealous and evil identical twin sister Agatha Cackle, who was seeking to turn all the teachers and pupils into frogs.
In The Worst Witch Saves the Day she once again saves the academy from the ruthless Agatha Cackle (who sneaked into the school disguised as a new teacher Miss Granite, with a high-pitched, squeaky voice, a huge cloud of orange curls, and an extremely bizarre personality) who tried to turn the whole academy into snails.
In the same book, Mildred also pulls off a daring rescue of her talking pet tortoise from a tall pine tree after Drusilla Paddock hid him there under Ethel's orders.
In The Worst Witch and the Wishing Star, as she starts fourth year, Mildred is promoted to Lantern Monitor of the school.
Although she has trouble training her cat, Tabby- who is grey with black stripes rather than the required black as they 'ran out of black ones' when handing out cats-, Mildred is nevertheless very fond of him, enjoying cuddling up to him in bed, and even risking expulsion to take him with her on holiday after she is forced to give him up in The Worst Witch All at Sea, and is upset when they suggest that her new dog Star replace Tabby as her broomstick companion until Miss Cackle clarifies that they intend for Tabby to remain as her general pet.
In the 2017 remake, Mildred is portrayed by Bella Ramsey (although in the episode "The Best Teacher", Mildred is portrayed by Rachel Bell when she is temporarily aged into an older woman by what was meant to be a wisdom spell) and by newcomer Lydia Page in Season four, after Ramsey left the series.
Both TV adaptations establish that Mildred is the 'worst witch' because she is the first student at Cackle's to originate from a non-magical background; the 1998 version has her receive a scholarship for an imaginative piece of creative writing and the 2017 version has her learn about Cackle's and magic because she helped Maud get to the school on her first day after Maud crashed into her balcony.
The 1998 TV series gave her surname as "Moonshine", but it is never referred to as this in the books; in fact Miss Hardbroom scathingly addresses her as Maud "Spellbody" in The Worst Witch All at Sea.
Enid Nightshade is Mildred's second-best friend who is introduced in The Worst Witch Strikes Again where she has hair "the colour of milky tea" wearing it in a thick plait and having large limbs.
[3] Ethel Hallow is the snobbish, stuck-up, vindictive, and sly rival and enemy of Mildred and her friends.
Various commentaries have noted that Ethel's primary weakness as a student is that, which she is able to easily follow the rules and perform new spells after the demonstration, she lacks the ability to imagine and improvise when given free rein.
This was demonstrated most clearly in The Worst Witch to the Rescue, when she was the student who performed worst in the art class and had no ideas whatsoever for a summer project to research a spell of the student's choice as she lacked a framework for her to start studying in, in contrast to Mildred who not only performed best in art but had even created a completely new spell for the project.
[4][5][6] The excuse for the change of actress, as explained in the first episode of the second series "Old Hats and New Brooms", was Ethel having a makeover (or a "witch-over" in their case) during the holidays.
[7] This version of Ethel is still intelligent, but is particularly driven to 'prove' herself as her elder sister Esmerelda is a third-year at Cackle's who is generally seen as the school's best student.
As the series continues, Ethel attempts to undermine Mildred and affirm her own place in the school, but her own nature often works against her as her attempts at 'heroism' typically involve making others look bad rather than putting herself at risk, such as stealing the school's Founding Stone to try and restore Esmerelda's magic after she was the reason her sister lost her powers in the first place, or creating a duplicate of Indigo Moon- another student from a non-witching background- that would attack the school so that Ethel could defeat the duplicate, unable to recognise the difference between building herself up and genuinely helping others.
Miss Constance Hardbroom is the extremely strict deputy headmistress and potions mistress at Cackle's Academy.