The Fragile Threads of Power is a 2023 fantasy novel written by New York Times bestselling author V. E. Schwab. The book is the first in a planned trilogy and was preceded by Schwab’s Shades of Magic series. The novel follows a cast of characters who reside in interconnected worlds: Black London, White London, Grey London, and Red London. The source of magic connecting the worlds appears to be slowly fading, fueling panic and political unrest. The novel’s themes include The Importance of Chosen Family, Defining Strong Leadership, and The Risks and Responsibilities of Power.

This guide references the 2023 Tor Books e-book edition.

Content Warning: The source text discusses violence, torture, and anti-gay bias.

Plot Summary

The Fragile Threads of Power takes place seven years after the events of the Shades of Magic trilogy, continuing the story of Kell, Lila, and Rhy and introducing several new characters. The novel takes place in four worlds, called Red London, White London, Grey London, and Black London. Black London once had magic, but it burned out and destroyed the citizens, almost destroying the other Londons as well. Grey London is a version of our world’s 19th-century London with no magic. Red London is a realm with plentiful magic, and White London’s magic is slowly being rekindled.

The Prologue begins in White London, where a young girl named Kosika narrowly escapes being sold into slavery by her mother and escapes into a forest, encountering a man’s body. The dead man is Holland Vosijk, the king of White London, though Kosika doesn’t know this yet.

Seven years later, in Red London, Alucard Emery, the king’s consort, worries over the spread of a shadowy organization called the Hand that seeks to overthrow the throne. An unnamed merchant’s son joins the Hand. He and two other men rob a magic ship called the Ferase Stras to retrieve an item called a persalis, which can make a doorway to travel between worlds. He alone escapes with the item. Maris, the ship’s captain, calls in a favor and asks Lila Bard to find the persalis for her.

Partners Lila and Kell are sailing on the Grey Barron. Kell is grappling with the loss of his Antari powers, the rarest and strongest kind of magic. They secretly board a ship from a warring country, but they are interrupted before they can discover what the ship is smuggling. After speaking to Maris, Lila agrees to find the persalis, and they set sail for Red London.

In the palace of Red London, an assassin unsuccessfully tries to kill the king, Rhy Maresh, intensifying Alucard’s search for the Hand. Alucard and the queen, Nadiya, try to track the organization through magic but are unsuccessful. Alucard worries that some of Nadiya’s inventions are too powerful and might be weapons in the wrong hands, but she chastises him for his fearful attitude.

The unnamed merchant’s son is feeling ill because of a curse from the Ferase Stras, though he does not realize this. He sees a repair shop sign in the London slums and stops to have the persalis repaired by Tesali Ranek. She has a rare gift for seeing and manipulating magic threads and runs the shop by herself. She is only 15 and fled her home country years before when her manipulative father and sister discovered her powers.

Tes agrees to fix the persalis and spends several days doing so before realizing its purpose when she accidentally opens a door into White London. She is horrified that such a dangerous device exists and attempts to destroy it. However, two criminals named Calin and Bex, who work for the Hand, arrive at her shop and demand to see the persalis. They kill the merchant’s son in an attempt to find it. Tes pretends to fix it but instead rigs a bomb and destroys her shop, escaping with the persalis. The bomb doesn’t kill her pursuers, and Calin catches up to her in an alley, stabbing her just before she uses the persalis to escape into Grey London.

In White London, Kosika now rules as child queen. Shortly after Holland’s death, she was discovered to have Antari powers and was crowned in the hopes that she would bring more prosperity. She has instituted a system of ritualized bloodletting to “tithe” to the land in hopes of restoring magic. She also sees a ghost who appears to be Holland, and he gives her advice on her reign. Some of the nobility see her as a child who can be manipulated, but she continues to establish herself as a leader, using violence when necessary. She has also managed to travel between the worlds to Black London and is terrified of the devastation she found there and what it could mean for her own world.

Kell and Lila arrive in Red London and visit the palace. Lila agrees to wander the streets and investigate while Rhy and Kell, who are adoptive brothers, spend time reminiscing together. She discovers that a coin Maris gave her from one of the thieves’ pockets has a code and an address on it. She also hears from a barkeep that the best place for repairs is a shop called Haskin’s.

Unbeknownst to Lila and her allies, the Hand’s leaders are meeting in a pleasure garden or sex work establishment called the Veil, which rotates houses every month and is difficult to track. Three conspirators meet to speak about their plan: Berras Emery, Alucard’s estranged brother, Ezril, the current high priest or aven essen, and the mysterious Master of the Veil, whose identity is not disclosed. They discuss Berras’s plan to use the persalis to kill Alucard and depose the king. They want to use the Hand as a weapon to bring revolution and then hunt down the lower-level members to use as scapegoats while they establish their power. None of the three leaders like or trust each other, and their conversation is contentious.

In Grey London, Tes manages to find a tavern where she sees some signs of magic. The owner and the barmaid heal her. Tes returns to Red London and decides to follow Lila Bard, reasoning that no one will capture her in the presence of a dangerous Antari. Lila realizes she is being followed and confronts Tes. Bex and Calin attack, and Lila and Kell fend them off, returning with Tes to the palace. Lila is angry that Tes will not try to heal Kell with her powers and has her taken to the dungeons. The queen releases Tes and offers her a place in the palace. However, Tes fears that the queen is like her father and escapes, only to be recaptured by Calin and Bex.

Tes is taken to the Emery estate, where Berras gives her poison and tells her she can only have the antidote if she creates a persalis for him in time. Despairing, she begins constructing a persalis that leads to an abyss between worlds, hoping to fool him and save her life.

Lila leaves the palace and realizes that the Veil is meeting that night. She infiltrates the meeting but is captured by Berras. He takes her to the Emery estate and tortures her, revealing his identity and that he has used one of Nadiya’s inventions to steal her magic for himself. Lila manages to use her magic ring to signal Kell for help.

Alucard and Kell head to the Veil but do not find Lila. The ring alerts them of her danger, and Kell transports them to the Emery estate to rescue her. Alucard and his brother duel while Kell rescues Lila from Bex.

Tes creates the false persalis, but Calin tests it and sees that it leads nowhere. He refuses to give her the antidote but is sucked into the abyss. The doorway grows stronger, endangering everyone. Lila and Kell arrive to try to stop it. Lila is not strong enough to close it alone, but Kell urges her to use Nadiya’s invention so that they can share power. She does so and manages to close the door, but the result shatters Kell’s remaining magic so badly that he is in constant, agonizing pain.

Lila heals Tes and asks her to try to heal Kell’s magic. Rhy agrees to take on the risk of death as well, as the brothers’ lives are magically bound, so Tes makes the attempt and heals Kell. Lila takes Tes to the Ferase Stras, where she becomes Maris’s apprentice.

At the palace, Berras is arrested and imprisoned. Ezril visits and kills him to maintain their conspiracy.

In White London, Kosika’s guards discover the remnants of the doorway Tes created. Kosika and Holland’s ghost discuss her fears about the walls between worlds crumbling. The ghost convinces her that Osaron’s fire is finally gone in Black London and that it will be safe to rekindle it, bringing magic back to their world. She agrees to try it.