Nathan fishes for flukes in the Living Mud with the Spark, an unpredictable and uncontrollable power he has inherited from his father.
The Spark Itches if Nathan doesn’t Scratch it.
One day he makes a limb-baby and sells it to a tanner.
Nathan takes the money to his poor mother and dying father.
The money is fake.
His mother orders Nathan to go to the Master for work.
The Fetch takes Nathan and some other boys up the Glass Road to the Master.
One of the boys is Gam Halliday.
Gam tries to recruit Nathan into his criminal gang.
Nathan refuses.
Gam goads Nathan into Scratching the Spark Itch by teasing him.
The Fetch beats another boy to death for the disturbance Nathan and Gam make.
The remaining boys are delivered to the Master.
Gam is rejected at the gate and returns home.
In the Underneath, Nathan saves a boy from falling to his death.
The boy is revealed to be a girl – Prissy – and Nathan feels an immediate sympathy with her.
The children are washed by a team of laundresses.
Bellows, the Master’s factotum, examines the boys, discarding some, including Prissy, and takes the others to see the Master.
The Master hires some of the boys for unspecified work, but declines to hire Nathan.
The Master can sense Nathan’s power.
He warns him against Sparking and sends him back to the slums.
At home, Nathan’s father is dying of the lungworm.
Nathan wants to Scratch the Spark Itch, but his father forbids it.
Nathan promises to get medicine, but he has no money.
In the slums, Nathan Scratches the Spark Itch, angrily, to kill a fluke.
The fluke evolves into a rat, which bites Nathan’s hand. From then on, Scratching the Itch burns the wound and makes Nathan’s arm increasingly immaterial.
Nathan goes into the Merchant City, hoping to steal money for medicine.
He steals a wealthy old woman’s coin purse, but is caught by bystanders.
Gam rescues him before he can be punished and takes him into the sewers.
The two boys go to Gam’s hideout, the clubhouse, an abandoned subterranean gentlemen’s club.
Prissy and Joes, the other members of Gam’s gang, are there.
Nathan, having fallen for Prissy, joins the gang.
The gang go back to the Merchant City on a job to steal money from a haberdasher.
Nathan panics when Prissy seems to be in danger and almost kills the haberdasher with the Spark.
With the money they have stolen, the gang go to see the gangmaster, Mr Padge, to buy the medicine for Nathan’s father.
Mr Padge gives Nathan the medicine, but refuses to take his money, establishing a debt on Nathan’s part.
Nathan returns to the slums. His mother is entertaining a gentleman caller with a fawn-coloured birthmark.
Nathan gives his father the medicine, but it’s clear that it won’t be enough.
Nathan agrees to get more.
Unable to bear being at home, Nathan returns to the clubhouse.
The pain of the rat bite gets worse, as does his Itch.
At night the clubhouse is full of ghosts who seem to recognise him.
The next day, Gam takes Nathan to steal bacon from a warehouse.
From there they go to the Temple of the Athanasians, a brothel where Prissy’s sister works.
Prissy will be sold to the brothel unless she can compensate her sister for the lost income.
Nathan agrees to a risky criminal job for Mr Padge in order to get the money for medicine and Prissy’s buyout.
Gam, Prissy and Nathan go to burgle a palace by entering through the sewers.
Nathan uses his Spark to open a safe and retrieve the document Mr Padge hired them to steal.
On the way out, Gam pushes Prissy into a crowded room and indicates that Nathan should rescue her by using the Spark.
In the room are various nobles, the chief of whom is the man with the fawn-coloured birthmark.
Hiding his surprise and horror, the man allows the children to leave before Nathan can kill everyone with the Spark, and gives him a gold coin.
Back at the clubhouse, Prissy questions Gam’s actions, but he won’t be drawn.
The gang take the document to Mr Padge, who gives them another job – to steal a locket from a merchant’s house.
Prissy uses her share of the money to pay off her indenture.
Scoping out the next job, with time to kill, the children visit the zoo and give buns to the alifonjers, Prissy’s favourite animals.
The gang decide to burgle the merchant’s house by going in from the roof.
They bribe the Fetch to take them up the Glass Road, slipping out near the roof of the merchant house.
Gam agrees to lower Joes, Nathan and Prissy down to the roof by rope.
Nathan, then Prissy, successfully make the rooftop, but Joes, seemingly betrayed by Gam, falls and dies.
Nathan tries to resurrect Joes using the Spark, but it doesn’t work.
The remaining children have no option but to complete the burglary, but inside they are interrupted by the magical dogs Sirius and Anaximander.
Anaximander, who can talk, threatens the children with death, and Sirius eats the faces from Joes, whose one body has become two bodies.
Nathan and Prissy return to the roof and attempt to descend to ground level by rope.
They are left dangling above a fatal drop: the rope is too short.
Having received new instructions from the Master via Sirius’s magical organ, Anaximander rescues the children.
The dogs accompany the children away from the merchant house, having secured the locket Padge hired them to steal.
The party go to find Gam, hoping for answers regarding the death of Joes.
They find Gam in a gin-house, but he is unwilling to talk.
The gin-house patrons attempt to steal Anaximander – he disembowels one of them and they give up.
The gin-wife objects to the mess Anaximander has made, and the dog agrees to provide a service for her.
Nathan, Prissy and Sirius go to the slums.
Nathan has no medicine for his father, who has become even more seriously ill.
Nathan’s mother begs Nathan to use the Spark to purge the lungworms.
Nathan agrees, revelling in his disobedience.
The procedure starts promisingly, until Nathan’s father rises up and prevents it.
Nathan’s mother urges Nathan to defy his father and cure him, but Nathan cannot break his father’s interdiction.
He promises to get more medicine and runs to Mr Padge.
Padge has kidnapped Gam and is holding him hostage until Nathan gives the locket they stole from the merchant house.
He also wants him to sign the document they stole from the palace.
Nathan isn’t interested, he only wants medicine.
Padge takes Nathan to the house of a pharmacist, and the two extort medicine from him with menaces.
Nathan hands over the locket and signs the document, which he cannot read, paying his debt to Padge and releasing Gam.
On release, Gam admits he let Joes fall and die on the orders of Mr Padge, who had threatened to have his assassins kill and mince Prissy.
Sirius alerts Nathan to the fact that his father is in danger and the party run to the slums.
There they find Bellows and a contingent of gill-men.
When Nathan reaches his father, he is dead.
Without his father’s influence restraining him, Nathan fills with the Spark.
The gang are summoned by a signal back to the clubhouse, where they find the ghosts of Joes, who warn Nathan against a trap.
Nathan, feeling that Bellows has killed his father on the instructions of the Master, vows revenge regardless of any trap.
Nathan begins to glow blue with Spark energy and his arm loses its materiality.
The gang go to the Fetch and threaten him with murder if he doesn’t take them up the Glass Road to the Master.
Reluctantly, he agrees.
They are met at the door of the Master’s manse by the Master and Bellows.
The Master denies the murder of Nathan’s father and forces Mr Padge, Prissy and Gam to admit that they were part of a plot against Nathan instigated by the Mistress of Malarkoi, the enemy ruler of a neighbouring city.
Unable to understand their treachery, Nathan turns his back on his companions and goes with the Master into his manse.
The Master has created a talisman – the Interdicting Finger – from the locket Mr Padge had them steal, combined with Nathan’s father’s severed index finger.
He puts this around Nathan’s neck, which calms his Spark.
The Master gives Nathan an ointment for his arm and leaves him in the care of Bellows.
Bellows begins Nathan’s education.
Nathan learns of Malarkoi, the enemy city, and its Mistress.
He is given educational toys that teach him how to behave.
Whenever he feels trapped, or angry, or violent, the locket around his neck dampens his spirits.
He is fed, watered, clothed, and indoctrinated in the ways of the Master of Mordew.
Nathan is given a magical book that teaches him how to read and write.
In the background to this new life, he sees fleeting glimpses of a girl in a blue dress.
He no longer feels the Itch to use the Spark.
Magical artefacts manipulate Nathan into believing his friends betrayed him.
When he learns that Prissy tricked him into loving her, he goes to the zoo and kills her precious alifonjers.
The next day the Master comes to him with a magical dagger and shows him how to use it.
Convinced the boy is under his control, he removes the locket that contains the Interdicting Finger.
Nathan is given the magical book, and the dagger, and is sent to Malarkoi to destroy its Mistress.
The book catalyses or inhibits his Spark, the dagger directs his violence.
In Malarkoi, Nathan meets the Mistress.
She is expecting him and seems resigned to her defeat at his hands.
She fights him nonetheless, and steals parts of his body to make a magical knife of her own.
She summons the gods of Malarkoi to defend her.
On the verge of his defeat, the book catalyses Nathan’s Spark and burns everything but the Mistress away.
Seeing she is defeated, she offers her life to Nathan, and asks him to give the knife to her daughter, Dashini.
Nathan kills the Mistress and lets out an unrestrained burst of Spark energy that scours Malarkoi for miles around.
Using the Spark in this profligate manner reduces Nathan’s material presence.
Nathan returns to a hero’s welcome in Mordew, the Master heals him, but Nathan knows himself to have been manipulated.
The Master sends him to see the girl in the blue dress, the imprisoned daughter of the Mistress of Malarkoi, Dashini, captured behind a sphere of magical glass.
Dashini has spent her captivity unsuccessfully inventing magical methods of escape.
She has made masks that allow her to possess some of the Master’s staff.
She gives one to Nathan, and that night they possess the Manse’s Caretaker and Cook.
Nathan takes her to the library, where the Master has stored some magical books.
Dashini uses one to summon the ur-demon, Rekka.
Rekka, determined to destroy its summoner, destroys the glass quarantine that has been imprisoning Dashini.
Dashini, free, transports Rekka to the centre of the Earth, and she and Nathan try to leave the manse.
The Master has magical barriers that prevent them from leaving.
Dashini takes them below to a chamber in which the corpse of God – the source of the Master’s power – is contained.
Nathan takes God’s eye and uses the power to return to the slums.
No longer constrained by the locket, and empowered by the eye of God, Nathan brings revolution to Mordew.
He creates an army of flukes from the Living Mud, sets fires, drives the slum-dwellers into the Merchant City, and then destroys the Glass Road.
Each act makes him less and less materially present in the world.
He reunites with Gam, Prissy and Sirius, and finds his mother.
She has joined forces with Anaximander, and takes them all to the man with the fawn-coloured birthmark.
This man has access to a merchant vessel, and the party leave Mordew burning behind them.
When the ship is at sea, Bellows boards with a group of gill-men, determined to bring Nathan back to the Master.
Nathan is exhausted by his use of the Spark, and the eye of God, and is now defenceless.
Mr Padge, who has stowed away on the ship, emerges with Prissy as a hostage.
Nathan agrees to return with Bellows peacefully if Bellows rescues Prissy.
Bellows takes a magical weapon and attempts to kill Padge, but Padge has magical protection.
The weapon’s effect is turned on Bellows, devolving him back into a boy.
While Padge is gloating over his victory, Gam stabs him in the back in revenge.
This was Prissy’s plan all along, she providing the necessary distraction that allowed Gam to sneak up.
Padge dies.
Nathan goes to comfort Bellows, but the Master appears and takes Nathan away.
Taking advantage of Nathan’s lack of material solidity, the Master crushes him.
Once Nathan is compact enough, the Master empties the locket he’d previously kept Nathan’s father’s Interdicting Finger in, and replaces it with Nathan’s remains, creating an artefact he calls the Tinderbox.
It had been the Master’s plan all along to make Nathan overexert himself, magically, so he could make this Spark weapon, which he intends to use against the Eighth Atheistic Crusade – the militant wing of the mysterious ‘Assembly’ – who are approaching Mordew, intent on destroying it.