Xaphania tells of the beginnings of the subtle knife and the start of the city of Cittàgazze. The story of the guild of the Torre degli Angeli and their stealings of the gifts of other worlds and also of the Spectres entering the world (showing someone being consumed by them). While staring at the tower, Lyra asks Will how they can get into it. They decide to look closer for a way in. Meanwhile, John Parry continues to summon Lee Scoresby using his mother's ring. Lee makes his way by boat up the Yenisei River looking for Grumman and they soon find his dæmon who leads them to him.
Still looking for the entrance to the tower, Lyra and Will decide to widen their search. In Oxford in Will's world, Oliver Payne tells Charles Latrom about their discovery of Dust and conciousness. Boreal tells them that he could get the Dark Matter Research Unit some defence funding. However, Mary Malone who talks to him sends him away. Mary tells Oliver that they can't let the research fall into the wrong hands.
Pantalaimon points out to Lyra a door with an angel on that she thinks might lead them to the Torre degli Angeli. She calls Will and they enter. Meanwhile, Lee and Grumman (who tells Lee to call him Jopari) meet each other and Grumman tells him why he summoned him: about the knife (which could cut between worlds and kill immortals) and that they need to find the new bearer of the subtle knife and show him to Lord Asriel in order to make sure his side (fighting for conscious beings) wins the upcoming war. Lee tells Grumman that he isn't interested in helping Asriel but in helping Lyra whom he loves. After entering the tower, Will and Lyra go to one of the upper floors where they find Giacomo Paradisi bound.
Paradisi tell them about a boy who stole the knife and the two untie him before Tullio confronts them. Lyra tells him that they need the knife but he tells them to go, swinging the knife and cutting two wings of a statue of an angel. Will goes to fight him and manages to make sure he loses the knife before Tullio pushes him out of the window. They wrestle and Lyra heps Will back inside. As Pan gets the knife, Tullio kicks him (hurting Lyra) before picking up the knife, swinging it, and cutting two of Will's fingers off. After being urged on by Paradisi, Will boxes Tullio and gains the knife leaving Tullio to flee. Will then faints.
After coming to, Paradisi tells Will that losing his two fingers shows that he is now the bearer of the subtle knife. Jopari tells Lee that he left his world (with his wife and son in it) and that he became a scholar and a shaman. Lee tells him that if he gets Lyra under the protection of the subtle knife, he will take him wherever he needs to go. Jopari agrees but warns him that Lyra may be put in even more danger due to the tasks that the bearer must perform.
Paradisi instructs Will on how to use the knife: how to open a window and then seal it. After Will gives up, Lyra comforts him and Pan strokes his hand (much to Lyra's shock). Serafina Pekkala and Ruta Skadi gather to talk about the bombings of Ruta's homelands by the Magisterium. Serafina tells her that Lyra has gone through the window Asriel opened up and invites her to cross which she agrees to.
Given new strength, Will successfully cuts a window. Then, Paradisi tells him the rules of the guild: close all windows opened, never let others use the knife, don't use it for ignoble purposes, and keep it secret. Paradisi decides to go and die in peace. Carlo Boreal and Marisa Coulter meet and Carlo tells her that he has seen her daughter in another Oxford and that he had found a window. Carlo says that, as soon as Lyra has given him the subtle knife, he will give Lyra to Marisa.
Will and Lyra leave the tower as Giacomo takes a liquid before the Spectres come in order to kill himself. As the Spectres arrive, they turn away realising that he has died. Carlo shows Marisa the window and they step through into Cittàgazze. Tullio, now without the knife to keep away the Spectres, finds himself persued by them and tries to flee but is crept up on and consumed.
Lyra visits Will while he is in the bath and tells him that she's sorry for what has happened. She then tells him that the alethiometer told her that he was important. Will says that they need to get the alethiometer back by stealing it. Lee leads Jopari to his balloon and Jopari promises a wind which soon picks up sending the balloon towards the window in the North.
Mary tries to use the Cave another time to communicate with Dust. When she speaks to them, they answer her questions and instruct her to ask a question. In response to her questions, they tell her that they are shadows (and Dust) and is conscious. The Dust tells Mary that it is angels and that they have intervened in human evolution for vengeance. The Magisterium troops in the zeppelins guarding the window note mysterious figures out there: witches. Despite shooting at them, the witches get in and slaughter the troops before escaping through the window, into another world.
- Main article: His Dark Materials (TV series)#Cast
- Dafne Keen as Lyra Silvertongue
- Ruth Wilson as Mrs Coulter
- Lin-Manuel Miranda as Lee Scoresby
- Amir Wilson as Will Parry
- Ariyon Bakare as Boreal
- Andrew Scott as John Parry
- Simone Kirby as Mary Malone
- Ruta Gedmintas as Serafina Pekkala
- Jade Anouka as Ruta Skadi
- Remmie Milner as Lena Feldt
- Robin Pearce as Oliver Payne
- Sasha Frost as Reina Miti
- Lewis MacDougall as Tullio
- Terence Stamp as Giacomo Paradisi
- Bella Ramsey as Angelica
- Ella Schrey-Yeats as Paola
- Cristela Alonzo as the voice of Hester
- Kit Connor as the voice of Pantalaimon
- Sophie Okonedo as the voice of Xaphania
- Phoebe Waller-Bridge as the voice of Sayan Kötör
|His Dark Materials TV episodes|
|Series 1||Lyra's Jordan • The Idea of North • The Spies • Armour • The Lost Boy • The Daemon-Cages • The Fight to the Death • Betrayal|
|Series 2||The City of Magpies • The Cave • Theft • Tower of the Angels • The Scholar • Malice • Æsahættr|
|Other||Making His Dark Materials|