Chapter 18: In the Kitchen
At 7:30, the grandmother departs for the Dining Room with the two boys in her handbag. As she drops the boy into her bag, she reminds him that since he's a mouse, he should be able to use his tail to grab things and swing around. The grandmother sits down at their usual table and sees two long tables with the sign "RESERVED FOR MEMBERS OF THE RSPCC" (153). A waiter approaches and after she talks to him she quickly releases the boy. He runs along the wall and is about to cross the main entrance to the Dining Room when all of the witches pour in. As soon as they have all passed him he crosses the doorway and scampers into the kitchen as a waiter enters. Once in the kitchen, he hides for a few minutes to get his bearings. He sees a handle sticking out above him and flips himself so that he swings by his tail. He enjoys swinging for a while until he is distracted by a waiter coming in with food a customer has sent back. The waiter replaces the food but then has all of the other kitchen staff spit on it before bringing it back out.
Next, a waiter comes in and announces that all of the women from RSPCC, that is, the witches, want soup. The boy sees them place a huge silver soup pot on a bench and springs into action, swinging himself from his tail so that he landed on a high shelf. He quickly scampers over so that he is directly above the pot and pours the formula into it. A moment later, a waiter pours a large amount of soup into the basin as well and then puts the lid on it, preparing to take it out to the women.
Proud and relieved, the boy swings by his tail from handle to handle of the saucepans stacked on the high shelves. In his enjoyment, the boy had forgotten he was a mouse until a waiter yells, "A mouse! Look at that dirty little mouse!"(p.162) The waiters are thrown into an immediate frenzy trying to catch the boy. The boy drops to the ground and runs around; in a flash, part of his tail is cut off by a waiter. In a panic, he runs up the pants leg of one of the cooks. The cook starts to slap his legs, so as the waiters laugh and the cook yells, the boy scampers all the way up his leg and down the other. In the commotion of the cook pulling off his pants, the boy darts out of the pants leg, across the floor, and into a sack of potatoes. Once things have calmed down, the boy sneaks out of the potatoes and out the door.
He reaches his grandma without rousing any more panic and she congratulates him and bandages his tail. She puts him back in the bag with Bruno, who is eating a roll. Peeping out of the handbag, the boy sees that the waiters are now clearing the bowls from the witches' soup. The boy and his grandma watch the witches and talk together until they see Bruno's father approach.
Chapter 19: Mr. Jenkins and His Son
Bruno's father demands to know where his son is. The grandmother tells him again that he is a mouse, which Mr. Jenkins refuses to believe until Bruno speaks to him. Bruno, like the boy, celebrates the fact that he won't have to go to school anymore, and his father laments that Mrs. Jenkins will be afraid and that they will have to get rid of their cat. The grandmother explains to him who the witches are and they discuss how The Grand High Witch Of All The World looks so small and harmless. Bruno's father says that he is going to call his lawyers, but the grandmother cautions him that this could result in him being turned into something even worse.
Chapter 20: The Triumph
As Mr. Jenkins storms off, The Grand High Witch starts to scream. She stands on her chair and then her table waving her arms and screaming, and then the other women start to scream, and then they all stand incredibly still. Everyone in the dining room watches as they turn into a swarm of brown mice. The women scream and the men shout and the waiters attack the mice with chairs and bottles. The children in the dining room laugh and clap.
The grandmother decides it is time to go. She drops Bruno off with his mother and father and then walks across the hotel lobby and right out the front door. She asks for a taxi and they get inside. She asks to be driven to the station and tells the boy that they are going back to Norway. The taxi driver is not scared by the talking mouse who the woman says is her grandson—he even makes a joke. She pets the boy's fur and they talk together about how well they have done.
Chapter 21: The Heart of a Mouse
Back in Norway, the grandmother and the boy invent a few things to make the house accessible for a mouse. Even though he is a mouse, the grandmother makes him brush his teeth and take a bath every night. One night, they talk about what may have happened to Bruno, thinking that his parents could have had him killed. Then, in the calm of the warm evening, they start to talk about when the boy might die, now that he has a mouse's body. Grandmamma says that mice usually live for only about three years, but that because he is a mouse-person, he might live for around nine. The boy is surprisingly happy about this, because he says he wants to die before his grandmother so that he doesn't have to live without her. They talk about how fast his heart beats as a mouse—so fast that you cannot hear individual beats but only a "soft humming sound" (190).
Chapter 22: It's Off to Work We Go!
Over dinner, the boy and his grandmother discuss the next steps to take in their plan to destroy all witches. The grandmother says that there must be another Grand High Witch by now, which upsets the boy; he feels as if his being turned into a mouse was for nothing if a new Grand High Witch can still keep control over all the other witches from other countries. However, the grandmother reveals to him that as soon as they got home from England she called the Chief of Police in Bournemouth and pretended to be the Chief of Police of Norway and got the Grand High Witch's address from the hotel. They realize that they can make plans to sneak in there, find out about all the other witches in the world, and take them all down one by one by turning them all into mice and releasing cats to catch them. The story ends with the grandmother and the boy anticipating much work and excitement ahead of them.
The boy does not have much time to explore life as a mouse, and so even during a time of extreme danger he shows the childhood delight in recognizing one's talents and identity. As he swings from his tail, he almost forgets where he is, which causes him to get hurt but not killed, perhaps representing the difficulties and ultimate triumphs of identity-formation in childhood.
Following the boy's success in the kitchen, it is interesting to compare the reactions of adult men, adult women, and children when they see the witches turn into mice. Dahl writes that, "All over the Dining-Room women were screaming and strong men were turning white in the face and shouting 'It's crazy! This can't happen! Let's get the heck out of here quick!'...Only the children in the room were really enjoying it. They all seemed to know instinctively that something good was going on right there in front of them, and they were clapping and cheering and laughing like mad" (180). Dahl again represents a gender difference he sees in society, and perhaps problematically reinforces this dichotomy for children, by specifying that the adult women in the room do not take action but only act helpless and frightened when a problem arises (except, of course, the grandmother). The adult men are also seen to be ineffective, but they must hide their emotions under words and proposed action. Children are shown to be intuitive and joyful, positive qualities that juxtapose the negative view Dahl has so far given of children other the protagonist in the character of Bruno Jenkins.
Similar to the section in which the boy compares the relative advantages of life as a mouse and as a human, with life as a mouse perhaps being the better of the two, here the boy has a discussion with the grandmother about death, in which he seems to possess both uncanny optimism about his situation and wisdom far beyond his years. The boy surprises the grandmother and likely the reader by saying that he is glad he only has around 9 years to live because he doesn't want to live without the grandmother. This might be a way of gently introducing to children the difficult, but unavoidable, topic of their own mortality.
Dahl also shows the reader how important motivation is to life. Though the grandmother and the boy have succeeded in their short-term goal and even come to terms with the fact that neither has long to live, they nevertheless proceed to make a complex, difficult plan to carry out for the rest of their days. Interestingly, they seem to see the destruction of all witches as purely their responsibilities, not trying to include the authorities of England, Norway, or any other country or authority, even though the grandmother is clearly comfortable contacting them. They may think that, as is demonstrated in their interactions with the Jenkins parents, they would not be taken seriously. At the very least, they see a way to execute their plan and want to get started as quickly as possible.
While the book's resolution ties up most of the plot, a few mysteries are left unsolved, mainly revolving around the grandmother. We are never given further details of the grandmother's own childhood encounters with witches. Most importantly, her missing thumb is never mentioned again after the two early mentions in the book, and the boy does not seem even to contemplate asking her. Perhaps, like the mouse-boy's chopped tail, the missing thumb was simply a momentary but tragic loss included by Dahl to represent the scars that one carries from childhood into adulthood.