In the prologue, Kovo is seen with his tribe of apes, thousands of years ago, before he was a Great Beast, as the Wyrm egg fell from the sky as a meteor onto the Evertree, creating the Great Beasts. Kovo discovers the Wyrm egg in the crater.
Abeke, Rollan, Tasha and Kirat arrive at the Place of Desolation, which turns out to be a volcano with chambers and halls cut from the inside. It is revealed by Shane that the place was placed on the axis of Erdas by the Hellans, so that birds are confused when flying past, much to Rollan and Essix's chagrin.They meet Niri, who has summoned Mulop. They communicate with Kovo through Mulop and Niri, Kovo explaining how the Evertree and the Wyrm fell.
Meilin bound Conor to stop him from escaping. She then heads to Takoda who communicates the message with Kovo. Soon, though, the bond between Kovo and Mulop breaks, and Meilin discovers Zerif has found them and is leading a fleet of ship there. However, they have problems of their own, as Briggan signals for them to come, as Conor had escaped and attracted a group of the infected. The Wyrm breaks free from its egg and descends while Conor groups the Many and leads them in an attack.
Xanthe returns with an army of Sadreans who haven't been infected yet. They successfully defended against Conor's forces with Kovo's help, and rang a bell, one that activated half the trap of defeating the Wyrm. The Wyrm then attempts an attack, but Kovo fends it off and it slinks off to find Zerif.
Rollan, Abeke, Tasha, and Kirat stay behind to protect children whom had lost their Great Beasts to Zerif, as to Shane's plan. Kirat, however, plans on escaping with the children, not including Tasha, Rollan and Abeke. Rollan and Abeke talk him out of it, and Abeke soon disobeys Shane's plan. She follows Shane, going with the archers. She attempts to fire at Zerif, but is blocked by Uraza. Meanwhile, Zerif kills a Redcloak. By this time, the Wyrm has arrived. It easily defeats a group of Redcloaks and pursues the survivors into the halls. Soon, a piece of rock knocked from the volcano from the impact of Zerif's cannonball flew into the room, Shane jumping on top of Abeke to protect her against it and knocking the rock out of the room.
Abeke is called for a message from Niri, to underground, where Rollan, Tasha, Kirat, Howl, and the children whom had lost their animals were. She receives the message, but then is interrupted by possessed Uraza trying to kill her. A mysterious Redcloak pushed the leopard onto the cavern wall, and Abeke notices yellow eyes behind the white mask.
Shane attempts to fight Uraza, but she has the faster reflexes. She bites his side and shakes him with her jaws, forcing Abeke to fire an arrow into Uraza, who flees. Shane promptly dies of a presumably pierced lung but has earned Abeke's forgiveness.
Zerif captures them while sending Uraza to passive state. Zerif, being power-hungry, boasts about his control over the Wyrm and is confident about using it to take over Erdas. The Wyrm turns the tables on Zerif, however, by restraining him with possessed Greencloaks. A vial Zerif was holding containing a Wyrm parasite shatters, but when it reaches the Wyrm the Wyrm absorbs it, revealing that the Wyrm parasites are actually pieces of the Wyrm's body. The Wyrm possesses Zerif and turns into what Abeke describes as "the Thing." The Thing has grey skin, black eyes, and writhing black veins. Tentacles shoot out of the Thing's fingers and drains the life from a Redcloak. It turns and attacks Rollan. Essix attempts to fight the Thing and is also captured. But when Abeke sent an obsidian pointed arrow towards a bell on a bell tower, ringing, for a brief moment, spirit animals and their partner's minds are reversed, and Zerif is in control of the Wyrm. Abeke begs him to kill the Wyrm, and he falls into the churning lava- the burning tide. The Wyrm attempts to climb out but sinks and dies in the lava.
The Wyrm is defeated, and all whom had been infected returned to normal. Due to the Wyrm being the creator of the spirit animal bond, when it died all of Erdas received the same energy the Evertree contains. Abeke noted that it made even baobab wood suitable for shaping a bow out of. The Sadrean and Erdas people reunite after thousands of years. Abeke and Rollan sail to Eura, where Meilin and Conor came back from underground. Abeke then sets out alone to find Uraza, and six months later, she arrived in Stetriol, finding a shameful Uraza, and begins to hunt with her happily.