The story is narrated from the perspective of an unnamed seven-year-old English boy, who goes to live with his Norwegian grandmother after his parents are killed in a tragic car accident. The boy loves all his grandmother’s stories, but he is especially enthralled by the stories about real-life witches who she says are horrific female demons who seek to kill human children. She tells him how to recognise them, and that she is a retired witch hunter (she, herself, had an encounter with a witch when she was a child, which left her with a missing thumb).
According to the boy’s grandmother, a real witch looks exactly like an ordinary woman, but there are ways of telling whether she is a witch: real witches have claws instead of fingernails, which they hide by wearing gloves; are bald, which they hide by wearing wigs that often make them break out in rashes; have square feet with no toes, which they hide by wearing uncomfortable pointy shoes; have eyes with pupils that change colours; have blue spit which they use for ink, and have large nostrils which they use to sniff out children; to a witch, a child smells of fresh dogs droppings; the dirtier the child, the less likely she is to smell them.
As specified in the parents’ will, the narrator and his grandmother return to England, where he was born and had attended school, and where the house he is inheriting is located. However, the grandmother warns the boy to be on his guard, since English witches are known to be among the most vicious in the world, notorious for turning children into loathsome creatures so that unsuspecting adults will kill them. She also assures him that there are fewer witches in England than there are in Norway.
The grandmother reveals that witches in different countries have different customs and that, while the witches in each country have close affiliations with one another, they are not allowed to communicate with witches from other countries. She also tells him about the mysterious Grand High Witch of All the World, the feared and diabolical leader of all of the world’s witches, who visits their councils in every country, each year.
Shortly after arriving back in England, while the boy is working on the roof of his treehouse, he sees a strange woman in black staring up at him with an eerie smile and quickly registers that she is a witch. When the witch offers him a snake to tempt him to come down to her, he climbs further up the tree and stays there, not daring to come down until his grandmother comes looking for him. This persuades the boy and his grandmother to be especially wary, and he carefully scrutinizes all women to determine whether they might be witches.
When the grandmother becomes ill with pneumonia, the doctor orders her to cancel a planned holiday in Norway (she and her grandson had planned to go there). The doctor explains that pneumonia can be very dangerous when a person is 80 or older (she later reveals in the book that she is 86), and therefore, he cannot even move her to the hospital in her condition. Instead, about two weeks later when she has recovered, they go to a luxury hotel in Bournemouth on England’s south coast.
The boy is training his pet mice, William and Mary, given to him as a consolation present by his grandmother after the loss of his parents, in the hotel ballroom when the “Royal Society for the Prevention of Cruelty to Children” show up for their annual meeting. When one of them reaches underneath her hair to scratch at her scalp with a gloved hand, the boy realizes that this is the yearly gathering of England’s witches (all of the other women are wearing gloves as well), but he is trapped in the room.
A young woman goes on stage and removes her entire face, which is a mask. The narrator realizes that this is no other than the Grand High Witch herself. She expresses her displeasure at the English witches’ failure to eliminate enough children, and thus demands that they exterminate the lot of them before the next meeting. She exterminates a witch who questions whether it will be possible to wipe out all of Britain’s children.
The Grand High Witch unveils her master plan: all of England’s witches are to purchase sweet shops (with counterfeited money printed by her from a magical money-making machine) and give away free sweets and chocolates laced with a drop of her latest creation: “Formula 86 Delayed-Action Mouse-Maker”, a magic potion which turns the consumer into a mouse at a specified time set by the potion-maker. The intent is for the children’s teachers and parents to unwittingly kill the transformed children, thus doing the witches’ dirty work for them so that nobody will ever find the witches because they are unaware that it was their doing.
To demonstrate the formula’s effectiveness, the Grand High Witch brings in a child named Bruno Jenkins, a rich and often greedy boy lured to the convention hall with the promise of free chocolate. She reveals that she had tricked Bruno into eating a chocolate bar laced with the formula the day before, and had set the “alarm” to go off during the meeting. The potion takes effect, transforming Bruno into a mouse before the assembled witches.
Shortly after, the witches detect the narrator’s presence and corner him. The Grand High Witch then pours an entire bottle of Formula 86 down his throat, and the overdose instantly turns him into a mouse. However, the transformed child retains his mentality, personality and even his voice – refusing to be lured into a mouse-trap. After tracking down Bruno, the transformed boy returns to his grandmother’s hotel room and tells her what he has learned. He suggests turning the tables on the witches by slipping the potion into their evening meal. With some difficulty, he manages to get his hands on a bottle of the potion from the Grand High Witch’s room.
After an attempt to return Bruno to his parents fails spectacularly (mainly due to his mother’s fear of mice), the grandmother takes Bruno and the narrator to the dining hall. The narrator enters the kitchen, where he pours the potion into the green pea soup intended for the witches’ dinner. On the way back from the kitchen, a cook spots the narrator and chops off part of his tail with a carving knife, before he manages to escape back to his grandmother. The witches all turn into mice within a few minutes, having had massive overdoses just like the narrator. The hotel staff and the guests all panic and unknowingly end up killing the Grand High Witch and all of England’s witches.
Having returned home, the boy and his grandmother then devise a plan to rid the world of witches. His grandmother, by impersonating the chief of police of Norway on the telephone, discovered that the Grand High Witch was living in a castle in that country. They will travel to the Grand High Witch’s Norwegian castle, and use the potion to change her successor and the successor’s assistants into mice, then release cats to destroy them. Using the Grand High Witch’s money-making machine and information on witches in various countries, they will try to eradicate them everywhere. The grandmother also reveals that, as a mouse, the boy will probably only live for about another nine years, but the boy does not mind, as he does not want to outlive his grandmother (she reveals that she is also likely to live for only nine more years), as he would hate to have anyone else look after him.
Yep, still as good as when I read it back in ’12 and the many times in the 90’s as well.