The story begins with a flashback. Nedwin, a 13-year-old squire, watches in dismay as the enemy systematically and brutally kills his comrades in their quest to capture Prince Galloran. The leader of the attack, Groddic, holds the last of the prince's men hostage. Galloran attacks by throwing orantium, an explosive mineral. The resulting flash temporarily blinds his opponents. Groddic challenges Galloran to a duel. The prince handily fights the conspirator, but at the last moment, Groddic throws a powder into the prince's eyes, which blinds him. Prince Galloran is captured.
Nedwin is heartbroken at his hero's defeat. Galloran had entrusted him to deliver information to other rebels should the prince fall. However, the boy also has an orantium sphere. In a desperate attempt to save Galloran, he hurls the explosive toward Groddic. The conspirator manages to catch the orb lightly in his hand so it doesn't detonate. Nedwin is brought down with an arrow, ashamed of his failure and hoping for death.
The story resumes in present day Lyrian, a world beyond Earth that is still ruled by the evil emperor Maldor. Rachel, a teenager from our world, is awakened by a call for help from Kalia, a girl she's been training in Edomic. Edomic is the language of creation in Lyrian, and those who have the ability can use the language to wield great power. When Rachel arrives in the training room, an Edomic command is spoken that freezes her in place. A spike is hurled toward her chest. She and Kalia lock in a battle of wills until Rachel is able to force the spike away. Kalia attacks with a knife in one hand and a long needle in the other. Rachel overpowers her. The girl admits she works for Maldor before injecting herself with lethal poison.
The following day, Rachel, her fellow Beyonder, Jason, and their various comrades set out on their separate quests to fulfill the oracle of Mianamon's prophecy. Rachel and Galloran, along with Nedwin, Ferrin, Tark and Nollin must gather an army to lay siege to Maldor's fortress at Felrook. Jason, along with Galloran's daughter, Corrine, the semi-giant Aram, and the Seed people Farfalee, Jasher and Drake, will pursue information from another prophecy that may help in the war.
Rachel and Galloran meet secretly with Chancellor Copernum, a member of the ruling class of Trensicourt. Galloran hopes to negotiate a peaceful turnover of power from the regents who reigned while he was prisoner. Copernum is not swayed to give Galloran back his throne until Rachel utters an Edomic command, which renders the chancellor unable to move. Another of Galloran's servants makes a slicing gesture across Copernum's throat. The meaning is clear: If Copernum and the other rulers do not relinquish their power to Galloran, they will be killed.
Jason and his friends must find their way into the city of Durna in order to steal a boat so they can travel to the Celestine Library. The plan is to wait until the Valiant arrives in port and steal it. It is an interceptor, one of the three fastest ships in Maldor's fleet. After several days, the Valiant arrives in port. Jason and his friends succeed in hijacking the ship with minimal losses to their own crew. They also set fire to the port, destroying the other vessels to keep them from chasing the Valiant. Soon the rebels are on their way to Windbreak Island where the Celestine Library waits.
After he is crowned, Galloran speaks to his subjects. He explains that although he accepted Maldor's gift of displacer eyes so he could see again, he never swore fealty to the emperor. Galloran only wanted the eyes so that he could see to lead the war against Maldor. He then explains about the prophecy and how, because of the oracle's words, he will begin the war against the emperor as soon as possible. The people of Trensicourt will not stand alone as other humanoid species of Lyrian, including the drinlings, and the Amar Kabal (Seed people), will join in the fight.
Maldor is able to establish a mental connection with Rachel. The emperor is able to read the girl's mind, learning about the oracle's prophecy and where Jason is heading in the interceptor. Maldor teases her with the fact that now that he knows their plans, they have even less chance of succeeding. He makes her an offer. If she will come to Felrook and become his disciple, he will allow her to choose 10 of her friends to be safe from his retribution. He will even allow Jason to return to the Beyond. Rachel need only commit to his teaching and be willing to have certain safeguards implanted in her mind so that if she chooses to betray him at a later time, Maldor can kill her. The emperor does not require her to answer immediately. He will know her answer when she comes to Felrook. Ferrin later assures Rachel that the emperor could have tampered with any of their party in order to discover their plans. He helps her to clearly evaluate Maldor's offer in terms of the price she'll have to pay as it compares to the reward she will receive.
Jason and the others arrive at Windbreak Island. They must defeat the guardian of the Celestine Library, the Maumet. As the first launch approaches the shore, the Maumet strides forward. It is similar to the featureless appearance of the lurkers, but bigger. Arrows, punches and swords have no effect on it. The beast is able to change its composition. Even orantium cannot hurt the creature. The first attackers retreat back to their launch after losing four drinlings to the combat. They notice the creature prodding the victims on the sand. Its body shifts into the various material it touches — leather, muscle, the iron of a weapon. Jason comes up with a new plan. An orantium sphere is broken within a bucket of special gel. The gel does not allow the explosive to ignite. As the Maumet reaches into the bucket, it turns into orantium. Since the mineral ignites as soon as it is exposed to air, the Maumet explodes.
Jason and the others go to the Celestine Library. Jason finds a holographic guide, Bactrus, who tells him of Darian the Seer's history. Bactrus warns that no one has been able to successfully follow the clues within the library's texts. The fate of Jason and his friends will be the same — unless one of them knows an ancient language known as Petruscan. Farfalee readily admits that she does, as she studied it in one of her earlier lives. Bactrus locates the Petruscan scroll, and Farfalee translates it for the others. As the scroll has never been read before, they don't know whether it is a fake document or real clue. The only way to tell is to follow the directions. Bactrus leads them toward the map room so they can copy a map of the Fuming Waste, the land where Darian the Seer lies. Cries echo through the library, and Jasher goes to investigate. Aram and the drinlings have spied six enemy ships heading toward the island. He has gone to prepare the Valiant for a quick departure as soon as the others have the information they need.
Several days after their escape from Windbreak Island, a commotion wakes Jason. When he goes on deck, he spies the lurker that everyone else is watching. It is walking on the ocean toward the boat. When the lurker, a torivor, chooses Jason, Drake jumps in to fight for him. Jasher also joins the battle. Drake makes a desperate run toward the torivor and is stabbed through the chest. Jasher stabs the lurker through the back and it disappears in a flash of light. Jason grieves Drake's death.
Rachel wishes she could find evidence that the prophecy they've hinged their hopes on may be false. She believes Galloran's faith in the prophecy may be the weapon Maldor uses to destroy them. Galloran argues that her doubts about the prophecy may be used the same way. Rachel wonders how he copes with his doubts. Galloran explains that first he searches for a better solution to the problem, but all agree there is none to this dilemma. Then he examines what he knows is true. Since he believes the oracle was not deluded or lying, he must accept that they have a chance to succeed. The conversation with the king helps overcome her doubts. Rachel decides she would rather die helping her friends than abandon them.
Galloran meets with the leaders of the rebellion as well as Rachel, Tark and Ferrin. Galloran fears if they wait to attack Felrook, they will forfeit the only possibility they have to win. Others believe Maldor will cut off any escape routes and slaughter them on the plains. Galloran insists that if they take Felrook, they can survive. Just because they don't know what information Jason will find to help their cause doesn't mean it can't exist. As the meeting disbands, Ferrin informs Rachel of Drake's death. She is devastated and wants to use her Edomic powers to lash out. Galloran stops her. If she weakens herself now, she will be useless when the battle begins.
Imperial soldiers are hot in pursuit as the Valiant approaches land. Jason, Aram, Jasher, Corinne and Farfalee take a launch onto shore along with drinlings. Another rider follows them, as they escape the port. It is Groddic. He threatens to kill them all, but they rush him and slaughter him first. Jason and the others travel over the desert-like landscape, following the landmarks on Farfalee's map.
Back in Trensicourt, Nedwin, whom Galloran appointed as regent, is overthrown by Lord Copernum and his cronies. Nedwin uses secret passages to safely escape. Although others try to persuade him to leave the city, Nedwin will not disappoint Galloran again.
Rachel begins to think the only way to find Felrook's weakness is to accept Maldor's offer so she can spy on him. Without telling the others, she sends her thoughts out to the emperor and tells him she'll become his apprentice, but he must tell her how she can get into the fortress. She then joins Ferrin and Tark in a council with Galloran. Torivors arrive with swords. She is carried by the lurkers into Felrook.
According to their map, Jason and his friends must enter the caverns to find Darian's last resting place. One of the drinlings abruptly kills Farfalee. He is not a drinling, but Groddic. Jasher realizes that Groddic is actually an ancient being known as the Wanderer. He has worked as Maldor's partner for many years. Jasher and the others battle the shape-shifting creature. Several of them die before Aram is able to defeat it. Corrine takes the seeds of Jasher and Farfalee so she can plant them. Jason must enter the waterfall alone to find Darian's last resting place. He is led down several corridors and must solve puzzles that seem to have been specially designed for him, until he is able to reach the vault where Darian's body lies. He finds a scroll addressed to him. In it, Darian expresses his gratitude for all Jason has done and the sacrifices all have made. Darian reveals the secret that can destroy Felrook. Jason must tell Galloran that Felrook rests on what was once Mount Allowat. Galloran will understand the message. Jason also needs to tell Rachel that Orruck, a creature she destroyed, has already taught her what she needs to know. Jason must use Ferrin's ear to immediately deliver the message or all will be lost. Darian shares a final prophecy. Should they succeed, then either Jason or Rachel must go back home. Lyrian will fall if they both stay or both leave it. Jason is instructed never to return to Darian's prophecy room. He will die if he tries. But if Maldor falls and Jason's daughter ever has need of him, a prophecy awaits her. Jason pulls Ferrin's ear out of his pack. He begs the displacer not to betray the rebellion but to deliver the message to Galloran right away.
Rachel is escorted to Maldor's apartment. She is surprised at his haggard appearance. He looks as if he's suffered a stroke. He tells her he wants honesty in their relationship, so he let her see what toll commanding the lurkers takes on his body. The effect is drastic, but temporary. Rachel tries to kill Maldor with Edomic commands, but he easily subdues her. Maldor speaks a command that renders Rachel unconscious.
Galloran remembers that Mount Allowat was an ancient site where orantium was mined. It was closed when a vein too large to extract was found. The mines were sealed and the location kept secret. Ferrin believes the lake was used to hide the entrance. He offers to search the lake. Galloran agrees to the plan. The king will try and get the Seer's message to Rachel. Tark asks to assist Ferrin in the search for the entrance and asks that should they find the vein, he be the one to ignite the orantium. It is a suicidal task, but Tark feels it is his destiny.
Back in Treniscourt, Nedwin seeks to assassinate Copernum in his sleep. Using his sword he cuts off the man's head, but the traitor doesn't die. Nedwin realizes that Copernum is a displacer. Copernum thrusts his own sword deep into Nedwin's chest. As Copernum gloats over the squire, Nedwin takes a vial from his neck and swallows its contents.
Meanwhile, Galloran is able to telepathically communicate with Rachel. He warns her to flee Felrook by the following day or she will die. When she questions if she can escape, Galloran tells her that she should use the command Orruck taught her. Once their communication is broken, Rachel tries to figure out a way to get out of the fortress. Orruck taught her the command for lightning, but it is extremely powerful, and she's never practiced it. The other command is how to turn rock into crystal, but she can't fathom how that will help her. Rachel remembers that Maldor wears a stone around his neck that gives him power over the lurkers. She breaks out of her room and finds the torivors. They tell her that while Maldor's pendant survives, they must remain in Lyrian. Rachel offers to destroy the stone if the 71 remaining lurkers will enter an agreement with her.
Nedwin wakes up, hanging from the castle gate as a warning to others who would try to usurp Lord Copernum. He had not swallowed poison in Copernum's bedroom, but plague worms. The worms devour their host's blood then reanimate the body as a kind of zombie. Nedwin sneaks back into the castle. Using secret passages, he finds his way to the dining hall where Copernum and his cronies are celebrating. Nedwin lobs orantium at the unsuspecting guards and guests. He uses the last sphere to kill Copernum before killing himself.
Maldor agrees to forgive Rachel if she will come out willingly from among the lurkers. She uses her Edomic training to turn Maldor's pendant into glass, then smashes it on the ground. A lurker emerges with two swords, but Maldor refuses to duel. The lurker swings his blade down to decapitate the wizard. Maldor is able to produce a force field that shields him from the torivor's attack. The lurkers promise that the one attacking Maldor will continue until the emperor is defeated. The rest take her to Galloran. She explains that she has a bargain with them. Five lurkers will remain in Lyrian — three to serve Galloran, one to serve Jason and one to serve Farfalee. The torivors will serve them unconditionally while the others go back to their home. When Rachel learns that Tark is in the mines, she asks that Galloran send a lurker in to save him. Before the torivor can leave, Felrook explodes, taking Maldor, and his armies, with it.
Five years later, Rachel prepares to leave Lyrian. Jason comes to her room to tell Rachel that the others are all gathered to say goodbye. Jason gives her a letter to deliver to his parents, explaining where he is and his decision to stay in Lyrian. He also wants her to give them some jewels and photographs of him. Rachel attends a feast with her friends before they escort her to the pool that acts as a passage between the two worlds. She returns to our world. Spying a farmhouse in the distance, she makes her way to it and knocks on the door. Rachel borrows a phone to call her parents. Their enthusiastic reaction cements her decision to come home.