Lyra trembles and moans as Pan presses himself into her bare chest. He notices the golden monkey quickly feel Lyra's body and discover the pouch on her waist. Mrs. Coulter offers Lyra tea, but Lyra begins to sob uncontrollably. While Mrs. Coulter comforts Lyra, Pan sniffs the drink and finds it innocuous. He thinks to Lyra that they must pretend in order to stay safe. Lyra answers Mrs. Coulter's questions and lies, saying that a couple kidnapped her from the party. She feels gradually stronger as she lies; it's something she knows how to do well. She accounts for her weeks with the gyptians, invents a stint as a maid at the bar in Trollesund, and hysterically asks why the doctors cut children from their dæmons.
It's unclear if the golden monkey is touching Lyra's skin (which would mean breaking the taboo) or not, but touching her is invasive regardless and drives home that although Mrs. Coulter might not be ready to let Lyra be a test subject, she's still more than willing to violate her privacy and treat her like an object or a pet. Lyra's sense of feeling stronger as she lies suggests that in a situation like this, when Lyra's wellbeing is on the line, lying isn't a morally reprehensible thing. Instead, it will let her get out of this alive. Further, it’s something that she’s good at and that feels comfortable for her, even in this otherwise strange and terrifying situation.
Lyra asks if it has to do with Dust and demands an answer. Mrs. Coulter says that Dust is bad and evil, and separating children keeps them safe from Dust. Remembering Tony Makarios, Lyra vomits. She says that if all adults have Dust it must be okay, and she points out that if Dust is so bad, Mrs. Coulter should've let them cut her. With a smile, Mrs. Coulter says the procedure isn't bad, and points out that the adults here have had their dæmons cut away. Lyra then understands the blankness of the nurses' dæmons. Mrs. Coulter goes on and says that after the cut, everything is peaceful. She says that during puberty, dæmons bring about "troublesome thoughts" that let Dust in. The operation means that one's dæmon becomes a wonderful pet. Lyra knows she's lying, and feels a flash of anger.
What Mrs. Coulter proposes is essentially that gaining experience by becoming an adult—and experiencing everything that comes with that, including the "troublesome thoughts" that are, presumably, a euphemism for sexual thoughts—isn't good at all. Instead, it seems as though Mrs. Coulter believes that a childish state of innocence is the best way to live. However, compare how Mrs. Coulter behaves to the way the intercised nurses behave. They're unfeeling and can't make their own decisions, which suggests that for an ambitious person, at least, Dust and experience are necessary.
Softly, Mrs. Coulter says that Lyra can sleep in here with her. The golden monkey paces, betraying Mrs. Coulter's impatience. Finally, Mrs. Coulter asks Lyra if the Master gave her an alethiometer. She says that it wasn't his to give, and that it shouldn't go to Lord Asriel. Lyra asks why, and Mrs. Coulter explains that Lord Asriel is doing evil and dangerous things. She unties the belt from Lyra's waist and pulls out the black pouch and then the tins. Lyra puts her feet on the floor as Mrs. Coulter, amused, opens the first tin and then the second. The spy-fly hurtles into the golden monkey's face, hurting him and Mrs. Coulter. Lyra and Pan race out of the room, set off the fire alarm, and set the kitchen on fire. Lyra grabs her furs and the alethiometer.
Telling Lyra that Lord Asriel shouldn't get the alethiometer ensures that Lyra will believe even more strongly that Lord Asriel should get it, given her idolization of him and her fear of Mrs. Coulter. In this way, Mrs. Coulter is unwittingly helping Lyra fulfill her destiny by making it seem even more important that Lyra get to Lord Asriel. In the same vein, saying that Lord Asriel's work is evil and dangerous makes it more likely that Lyra will decide that it must be good, since she doesn't trust Mrs. Coulter's interpretation of anything at this point.
Lyra and the children struggle to get out as the fire spreads. They manage to escape and find Roger. She tells him to tell the other children that the adults will cut their dæmons away—hoping to scare them into following her. They follow, but soon come face to face with the Tartar guards and their wolf dæmons. Lyra hesitates, but shouts at the children to throw snow at the Tartars' eyes. It works. The children run, but Lyra knows that the Tartars are preparing to shoot. They never do, however; arrows come from witches above. Children begin screaming as they catch sight of Iorek charging past them to crash into the Tartars.
Lyra demonstrates here that she's much better than the Bolvanger adults are at controlling a group of children. This offers another example that children can be powerful when they're given the right tools and the right situation. However, it's still important to note that the witches and Iorek ultimately save the children; they can't exist on their own without some degree of adult assistance.
The children excitedly follow Lyra away from Bolvanger. They're thrilled to be saved but disturbed when Lyra tells them about Tony Makarios and the ghostly dæmons. One child points back toward Bolvanger and Lyra sees Lee Scoresby's balloon, which he's inflating using the gas from the zeppelin. The children begin to shiver, so Pan bullies their dæmons into warming them. They trudge on, following Iorek's tracks. Lyra begins to hear and see strange things, and finally falls into John Faa's arms. She tells Farder Coram that Roger is coming and asks what the strange noise is. Suddenly, the golden monkey attacks Pan while Mrs. Coulter pulls Lyra onto a motorized sledge.
Now that Lyra has saved these children, they can presumably return home and broadcast what they've experienced in the north. This illustrates how something like the Magisterium can be taken down when individuals like Lyra speak out and spread the truth along secret channels, thereby sowing discord and distrust in the establishment.
Mrs. Coulter sets a group of Tartars on the gyptians and Lyra watches her wrestle with Roger. Suddenly, Iorek leaps into the fray and Lyra feels something pull her up. She grabs Roger and sees that witches are lifting her. She lands in Lee Scoresby's balloon and a moment later, Iorek crawls in. The balloon surges up through a cloud. When it rises above it, Lyra watches the Aurora ahead and the witches flying up from below. One beautiful witch flies up next to the balloon and says that she's Serafina Pekkala. Lyra realizes suddenly that Farder Coram loved the witch, and that it's breaking his heart to be so old when she's still so young and beautiful.
It's unclear here why Mrs. Coulter is trying to kidnap Roger specifically, especially since Lyra never shared with her that she knew Roger before. While this doesn't make sense now, it does later: Lyra needs to take Roger north to Lord Asriel in order to fulfill the prophecy, and Mrs. Coulter trying to kidnap him here ensures that Lyra takes special care of her friend. Realizing that Farder Coram's heart is breaking is another flash of maturity for Lyra.
Serafina Pekkala confirms that Lyra still has the alethiometer. Kaisa flies up and Serafina passes on that Bolvanger is in ruins, the children are safe, and Mrs. Coulter escaped. Lee Scoresby attaches a rope to his balloon, throws it to the witches, and six witches pull the balloon north. Roger and Iorek fall asleep. Serafina asks Lyra why she's going to Lord Asriel. Lyra incredulously says that she needs to take him the alethiometer. She amends this to say that they're going to try to rescue him, and asks why Serafina is asking. Serafina says that there are things she needs to tell Lyra after Lyra sleeps.
As far as Lyra is concerned, it's clear what she needs to do—but the fact that Serafina Pekkala is asking suggests that Lyra is, at least to a degree, misguided about what she's actually supposed to do. Regardless, Lyra's desire to help and save Lord Asriel speaks to her growing sense of responsibility to the people she loves, while asking Serafina why she'd ask this question shows her becoming more mature and shrewd in gathering information.