The Book That Broke the World

Mark Lawrence is an American-British fantasy writer of a number of bestselling fantasy series, including The Broken Empire, The Red Queen’s War, and the Book of the Ancestor trilogies. Since the publication of his debut novel, Prince of Thorns, in 2011, Lawrence has become a prominent figure in the grimdark fantasy subgenre, which is characterized by its depictions of graphic violence, realistic details, and psychological conflict that subvert the idealism of classic high fantasy. The Book That Broke The World, published in 2024, is the second in The Library Trilogy, which centers on a massive library that spans space and time and is at the heart of controversy about the use of knowledge, a conflict that becomes increasingly destructive over the course of the three books.

The Book That Broke the World begins with the protagonists of the first book separated by the disasters that assailed the library at the end of The Book That Wouldn’t Burn. A metafictional novel that questions The Costs of the Ongoing Cycle of Violence, The Dangers of Incomplete Knowledge, and The Healing Power of Peace and Alliance, The Book That Broke the World sets readers up for the concluding chapter in the library’s fate, The Book That Held Her Heart, published in 2025. 

This guide is based on the hardcover first edition of the novel, published in the US by ACE Books in 2024.

Content Warning: The source material and this guide feature depictions of graphic violence, racism, enslavement, death by suicide, and death.

Plot Summary

The Library Trilogy is set in Crath City and the surrounding desolate environment, called the Dust. Crath City is home to an extensive and enigmatic library that holds all the knowledge of this fantasy world. Within it, a feature called the Mechanism allows readers to enter the world of the book in their possession through a portal. Crath City and its surroundings are home to several species, including humans, cranith (wolf-like creatures), and ganar (small, furry, intelligent beings). 

This novel picks up where the previous book in the series, The Book That Wouldn’t Burn, ends, with its main characters, Evar and Livira, separated: Livira is in ghost form, able to witness the action within the library but unable to be seen, while Evar is again trapped within the library with his siblings, each in a different room. The Book That Broke the World introduces a new species, the ganar, and follows two particular ganar, brother and sister Hellet and Celcha. The novel operates in two timelines: Hellet and Celcha’s narrative present, represented by Celcha’s chapters, and a timeline set 200 years in the future, represented in Evar, Livira, and Arpix’s chapters. 

Hellet and Celcha were born into enslavement—they and their fellow ganar excavate the remains of an ancient civilization for their sabber enslavers, and live in a small community on the Arthran Plateau in the Dust outside Crath City. The ganar are a species of intelligent, fur-covered beings who are about half the size of humans. 

One day, while they are excavating the remains of an ancient city, Hellet discovers a library. A librarian comes from nearby Crath City and brings both the books from the excavated library and Hellet and Celcha to the library in Crath City’s center, an immense structure that holds books written by every species that ever existed on the planet. Some rooms in the library can only be opened by members of particular species, and the library needs a pair of ganar on staff. Celcha and Hellet are put into training to eventually assume positions in the library.

While humans, canith, and ganar all live in the city, the ganar are enslaved. Celcha and Hellet are given food and shelter while in training at the library, but Celcha still feels the ganar are not on equal social footing with the humans and canith, a larger, humanoid species with wolf-like aspects. Lutna, a human girl who is part of the royal family, is in training with them, and she attempts to befriend Celcha. She takes Celcha to visit the palace, where Celcha is treated cruelly by two royal princes. 

Since they’ve arrived at the library, Hellet has been reading books and communicating with two of the library’s resident ghosts named Maybe and Starve. He remembers the cruelties they have suffered and wants to change the social order. Celcha is concerned by her brother’s developing perspective, but at his request, while out in the city, she visits the city’s gas room, which furnishes the city’s light and heat and is run by the ganar. 

Two hundred years later, a young adult canith, Evar Eventari, leaves the library chamber where he has spent his life. The library is overrun by insectoids called skeer, which attack all other living creatures. Evar is pursued by an enormous mechanical construct, called an Escape, which seems intent on killing him. Along with his siblings, Clovis and Kerrol, Evar finds a way out of the library into the ruined city. They flee the city and arrive at a human encampment on the Arthran Plateau, which has an invisible boundary that holds back the skeer.

Meanwhile, a librarian named Arpix has been trapped in the encampment with other humans for four years, having fled the library when Crath City was attacked and overrun by a canith army. Arpix is cautious about harboring three canith, but Clovis, Evar’s sister, is injured. As Arpix tends to her and the group works together to escape the surrounding skeer, Arpix begins to wonder if human and canith can overcome their enmity through fighting a common adversary.

Evar is in love with Livira Page, a young librarian and Arpix’s friend, who ended the previous book as a ghost. Livira is still in the library as a ghost, and she is informed by an assistant, one of the marble-like eternal beings who manage the library, that a book she wrote and snuck into the library’s collection is a threat to the library’s well-being. With her soldier companion and fellow ghost Malar, Livira enters the pages of her book, a collection of stories. She is at first surprised by the arrival of a white-skinned child who shows up unexpectedly in the story, but Livira eventually recognizes the child as the lost daughter of Yute, a deputy librarian, who risked his life to help others escape the library when the canith attacked.

In the earlier timeline, Celcha agrees to help Hellet enact a plan to liberate the ganar. He has created flasks of quicksilver that he plans to pour into the city pipes through the gas room, creating a gas that will put humans and canith to sleep. During that time, he says, the ganar can be freed. However, after she helps him execute the plan, Celcha realizes that the poisonous gas has killed everyone in the city. She sees two ghosts, a canith man and a human female, embracing and believes they are Maybe and Starve, the ghosts that led Hellet to commit this terrible deed. Hellet becomes an assistant in the library, while Celcha vows revenge on the ghosts.

In the future, Livira, who believes in the library’s mission of making knowledge available to all, continues to search for a way to reunite with Evar. She and Malar encounter Mayland and Starval, two of Evar’s siblings, who are on a mission to destroy the library, carrying out an age-old war on behalf of the caniths. When Livira takes a portal back to the library, she discovers a ragged camp of humans led by King Oanold, who have taken refuge in the library. Oanold is furious that he was deposed and wants his kingdom back. Livira is horrified to realize that instead of using the library’s resources, Oanold and his soldiers have been cannibalizing people in order to survive.

Meanwhile, Evar, Arpix, and their group survive an attack by a group of destructive insectoids called cratalacs. They locate a mysterious orb that is able to repel the skeer and are able to leave their encampment and return to the library. There, they meet another group of humans, led by Yute, who explains that they are trying to avoid capture by Oanold’s men. Evar asks if they can look for Livira, and Yute’s cat Wentworth leads them through the library. They discover that Malar has been killed trying to protect Livira from Oanold’s men. As they discuss whether to flee or fight, Yolanda, Yute’s daughter, appears and informs them the library is breaking apart.

Yolanda leads them to a Mechanism, a library portal through which a person can enter whatever book they are carrying. There, the group confronts Irad, the library’s founder, whose original vision has been thwarted by conflict and compromise. He is opposed by his brother Jaspeth, who believes that the preservation of knowledge is an obstacle to progress and peace. 

Yute has been trying to achieve a compromise between the two men, but he carries his own guilt: When he helped the king and his party into the library to escape the canith army, he accidentally opened a portal into a library chamber where a canith clan lived. The king and the soldiers slaughtered the canith clan, Evar’s family, before Yute could transport them elsewhere. Clovis wanted to attack the humans in revenge, but Evar was injured helping her. In addition, when Clovis tried to help him, she accidentally activated a mechanical ganar that was programmed to attack Evar and Livira.

Two hundred years earlier, Celcha engineers the mechanical ganar. When she learns that the ghosts who convinced Hallet to destroy the city through the gas room have been found, she believes she can enjoy revenge at last. 

Now, however, her automaton destroys Hellet. His blood opens three portals in the floor that represent the three possible fates of the library: destruction, Irad’s original vision, or a path of compromise. Though Hellet is now a ghost, he and Celcha reunite. 

Two hundred years later, Livira and Evar are once again separated while the group members sort themselves into sides. In the concluding scene, Lord Algar, one of the king’s party, discovers that Livira’s book is causing the cracks in the library foundation. He approaches Arpix, who has been taken prisoner, for an explanation.