Part One
One year after the Battle of Thaylen Field, the Parshmen, now known as Singers, continue evolving and forming their own society through dominance and oppression as the Knight Radiants struggle to fend off Odium's influence. Kaladin travels to his hometown of Hearthstone to rescue the citizens, including his family, and to pick up a famous Herdazian general known as The Mink who has fled from Herdaz after the Parshmen conquest. Navani, Dalinar, and many Radiants arrive on a flying machine to assist Kaladin in evacuating the city. While the evacuation begins, the Radiants battle with the Fused, which ends inconclusively. Meanwhile, Kaladin is baited into a fight with his former friend Moash, who induces visions of traumatic experiences in Kaladin. With Renarin successfully distracting Moash, he helps Kaladin escape to the flying machine, and they fly away with the townspeople on board. While returning, Navani is contacted by a mysterious stranger who tells her that creating magic devices called fabrials is unethical. Fabrials are created by imprisoning a spren in a gemstone.
After returning to Narak, Dalinar relieves Kaladin of duty due to his battle shock and increasing depression. Kaladin searches for a way to continue serving those around him without fighting and starts assisting his father in the infirmary. He eventually finds greater purpose in helping those with mental issues through group therapy and more progressive treatments.
Meanwhile, Shallan and her split personalities infiltrate the Sons of Honor to curry favor with Mraize and the Ghostbloods. This clandestine organization hints at secrets beyond the world of Roshar. During the mission, Shallan discovers a hidden notebook mentioning mysterious terms (referring to other worlds in the Cosmere universe) and considers breaking free of the Ghostbloods. Mraize sends her on one final mission, promising her full Ghostblood membership and knowledge after she finds and kills Restares in Lasting Integrity, the honorspren's base in Shadesmar. Following the Mink's advice, Shallan, Adolin, and a few Radiants head to Shadesmar as diplomatic envoys to encourage more honorspren to bond with humans. Dalinar and Jasnah set off to fight on the Emul battlefront in a strategic maneuver, leaving Navani and Kaladin behind at their home base of Urithiru to manage matters. Taravangian supports the Emul battlefront, plotting for his troops to betray the rest of the human army on Odium's orders, though Dalinar foresees and plans ahead for this betrayal. After the battle, Taravangian is captured as a traitor and begins to see ways to thwart Odium through Nightblood, the black sword.
Led by Raboniel, who claims to have found a way to end the war permanently, the Fused invade and take control of Urithiru by corrupting the Sibling, the tower spren, causing all the Radiants in the tower except Kaladin and Lift to fall unconscious. Navani and the Sibling manage to activate a shield before the Sibling is fully corrupted, powered by four hidden nodes. Navani surrenders and is enlisted by Raboniel to aid in her research. Together, they discover that Voidlight and Stormlight can be mixed into Warlight. They also find anti-types of light, something that can permanently kill spren and Fused, a discovery that can end the cycle of war. Aided by Navani, the Sibling, and Dabbid, Kaladin escapes with an unconscious Teft to a hidden room in the upper levels of Urithiru. Kaladin's depression worsens, with Moash and Odium sending him visions to drive him to suicide, but he keeps busy defending the nodes under Navani's and the Sibling's instruction. Venli, Rlain, and Dabbid help take care of Teft and free Lift from the Fused, who can wake the unconscious Radiants with her healing powers.
Increasingly suspicious, Dalinar looks at Urithiru through the Stormfather and realizes the tower has been occupied by the enemy. He decides to seek out another Bondsmith, Ishar the Herald, to increase his powers and fight back. However, Ishar, driven insane through the centuries, attacks Dalinar. Defeated by Szeth, Ishar temporarily regains sanity and tells Dalinar to meet him in Shinovar for further instruction. Dalinar discovers that Ishar has been experimenting with spren bodies in the Physical Realm. Meanwhile, Shallan and Adolin travel through Shadesmar. Adolin undertakes a legal battle in Lasting Integrity to convince the honorspren that humans are worth bonding with again. Shallan realizes that Restares is actually Kalak, a Herald, and judge of the trial. She attempts to assassinate him but, in doing so, releases her repressed memory of killing her first spren, Testament. In the process of facing it, Veil, the personality Shallan created to infiltrate the Ghostbloods, is absorbed back into her. Adolin's dead Shardblade, Mayalaran, speaks at the trial, revealing that the ancient spren chose to sacrifice themselves with the Knights Radiant, discrediting the anti-human leadership of the honorspren and allowing new honorspren to enter Roshar to bond new Radiants. Shallan ends her association with the Ghostbloods and sets herself firmly against them.
Navani, Kaladin, Teft, and Lift fight to wake the Radiants and liberate Urithiru. Teft and Lift infiltrate the infirmary while Kaladin provides a distraction by fighting one of the Fused outside. However, Moash is waiting and kills Teft, then throws his corpse to Kaladin. Kaladin's father is thrown off the tower by another Fused. Consumed by grief, Kaladin jumps off the tower into the highstorm, where he is saved by Dalinar and the Stormfather. He states the Fourth Ideal and saves his father, then returns to reclaim the tower. Dalinar later recruits Kaladin to join him in Shinovar to help treat Ishar's mental issues. Navani encounters Moash during her escape attempt. He tries to kill Navani, but she bonds with the Sibling, becoming a Bondsmith. She repels Moash and reverses the tower's corruption through anti-Voidlight. Blinded, Moash flees Urithiru and is later reclaimed by Odium. The remaining Fused attack the infirmary; Venli teams up with Rlain, Leshwi, and the humans to protect the unconscious Radiants, showing that the singers and humans can live in harmony. She eventually reunites with an escaped group of listeners, including her mother, who are eager to bond with spren, redeeming herself and her past role in bringing about Odium. Dalinar meets with Odium in a vision, where Odium, shaken by the loss of Urithiru and the failure of so many of his plans, agrees to a contest of champions. Dalinar is able to manipulate Odium into swearing that whoever wins, Odium will enforce an end to the war and withdraw his influence from Roshar entirely. Szeth leaves Dalinar to pursue his next Ideal and visits Taravangian in his cell, intending to kill him once and for all. Before he can do so, Odium pulls Taravangian (and unintentionally Nightblood) into a vision, where Taravangian stabs Odium and kills his Vessel (the person who serves as the mind directing Odium's power), taking its place. The newly born Odium (who is still bound by the old Odium's agreements) tricks Wit, leaving him unaware of Odium's new identity.
