Catherine Fisher


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Incarceron Summary

SuperSummary, a modern alternative to SparkNotes and CliffsNotes, offers high-quality study guides that feature detailed chapter summaries and analysis of major themes, characters, quotes, and essay topics. This one-page guide includes a plot summary and brief analysis of Incarceron by Catherine Fisher.

The first in a duology of science-fiction/fantasy novels, Incarceron explores themes of freedom, imprisonment, love, and hope through the tale of a “living prison” and two young people’s attempts to escape their fates. The novel opens with Finn, who is a prisoner in a vast, artificially-sentient prison called Incarceron. Everyone believes that Finn was born in the prison when he awoke in a cell three years ago. However, Finn has memories of another time and place, making him believe that he entered the prison from the world outside. His friend Gildas believes that these are not true memories but clues sent by a mythical figure called Sapphique who is rumored to have escaped Incarceron many years ago.
To keep himself alive in this harsh prison world, Finn has joined up with a gang of thieves and cutthroats. During one robbery he saves a woman who sees his tattoo of an eagle and a crystal and claims to know the location of an item that resembles it.

Outside the prison, in a beautiful futuristic world artificially arrested in the seventeenth century, a young woman named Claudia is attempting to escape her arranged marriage to Prince Caspar, the son of the king and queen. She tries to persuade her father, the Warden of Incarceron, to cancel the ceremony. He refuses. She was previously engaged to the king’s elder son by his first wife, Giles, who died young. Claudia believes that the new queen killed him so that her own son, Caspar, would eventually become king. Wishing to access Incarceron, Claudia breaks into her father’s office and makes a hologrammatic copy of an eagle-shaped key decorated with crystal.

Back in prison, Finn and the gang exchange a captive for an object shaped like an eagle and decorated with crystal that mirrors Finn’s tattoo. When Finn’s not-entirely-trustworthy “oathbrother” Keiro asks him what it is, Finn realizes immediately that it is a key. This confirms his belief that he originally is from outside Incarceron. In the prison, the very concept of keys does not exist. Finn has a vision of Sapphique telling him to “unlock Time” by using the key in a shiny black doorway. Gildas says that he knows where the doorway is and they decide to escape, along with a reluctant Keiro. After fighting their way away from the gang, they find the doorway and use the key to escape into a mysterious metal forest, accompanied by the gang leader’s slave, Attia. Finn hears a voice coming from the key and speaks to Claudia, asking her to help him break out of Incarceron.

Meanwhile, Claudia is pulled into court politics when she is approached by a group known as the Steel Wolves who wish to overthrow the monarchy and move beyond the artificially-maintained seventeenth century. Later, as she reports this to her beloved teacher Jared, the key lights up and they hear voices which, to their confusion, sound scared and unhappy. This confuses them, because they believe Incarceron is supposed to be a wonderful, joyful place. Later, Claudia hears a rumor that Prince Giles was not killed but was hidden in Incarceron as a child. She also makes contact with Finn again and this time is able to see him. Their conversation reveals to her that Incarceron is actually a grim, tough, unpleasant place and that Finn greatly resembles the lost Prince Giles.

When a net drops onto Finn and Gildas, Keiro grabs the key and flees with Attia. Finn and Gildas are taken to a city decorated with pictures of Sapphique. When Gildas tells their captors that Finn sees visions of Sapphique they are given to “the Beast” as tribute. The Beast turns out to be a huge red eye that reveals itself as Incarceron. However, Keiro has spoken to Claudia through the keys and she has charged him with rescuing Finn, so he attacks Incarceron with a flamethrower and the group flee. They are rescued by a mysterious man in a flying ship who then demands the key. When Finn refuses, the man attempts to poison him but is unsuccessful. They are caught up in a storm and the ship is wrecked as they land.

Outside the prison, the attack on Incarceron sets off an alarm on the Warden’s watch and he goes to investigate. Claudia follows him and finds what she believes is the entrance to Incarceron. However, when she and Jared go through, they find only her father’s office, where Jared collects a strange speck or crumb off the floor. The Warden confronts Claudia and demands the key from her, but she also refuses. Later, Jared shows her the speck under a microscope, revealing a tiny zoo. They conclude that, like the zoo, Incarceron has been shrunk to a very small size, making it easy to hide.

Claudia deduces that the Warden is actually one of the Steel Wolves working to overthrow the monarchy. Later, speaking through the keys, Attia reveals that the Warden is not Claudia’s father and that Claudia was actually born in the prison and taken out when she was a baby. On the day of her wedding, Claudia manages to break into Incarceron and, despite the prison’s efforts, meets up with Finn. The Warden speaks to Finn and Claudia through the keys and explains that the queen knew he took Claudia from Incarceron and used this to blackmail him into making Claudia marry Caspar. He also tells them that the keys can each bring one person out of the prison. Finn promises to return for the others and then he and Claudia leave Incarceron.

The Warden tells the assembled wedding guests that Prince Giles has returned from hiding and will now marry Claudia. To escape the queen’s anger, he then uses the keys to transport himself into Incarceron. Finn realizes that he cannot go back into the prison to help his companions and must instead go through a sham wedding and take the role of “Prince Giles.” Despite Claudia’s assurance that they will solve that problem, as the novel closes, Finn concludes that he is as much a prisoner outside Incarceron as he was inside.