Thirteen-year-old Sophie Foster is an elf who spent most of her childhood living with a human family. She was unaware of her true identity. Sophie was created by a clandestine group named the Black Swan and hidden with humans in San Francisco, for reasons Sophie still doesn’t fully understand.
She was found by another elf, Alden, and his son, Fitz, and taken to live in a secret elven city. Unlike most elves, who have only one ability or none at all, Sophie has manifested multiple abilities and must learn to use and control them. She must also learn to live in an elven society that is alien to her.
The elven councilors ask Sophie and her friend Keefe to teleport to an animal sanctuary housing Silveny, the last female alicorn in existence, because they both have a bond with the animal. Silveny is not adjusting to her new home. When Sophie and Keefe arrive, they find the alicorn agitated.
Sophie finds the source of Silveny’s distress: a small tracker made from ogre technology attached to her tail. Elves and ogres have a tenuous peace treaty, but neither side trusts the other. Since no ogres were seen at the sanctuary, only a hooded figure who smelled like ash, Sophie and Keefe speculate that the rebels are working with the ogres. The rebels have at least one pyrokinetic — the illegal ability to start intense fires — with them.
Sophie and Keefe teleport to the city of Everglen and give Alden Vacker the tracker. He’s a diplomatic emissary to the council. Alden blindsides Sophie by telling her that the council has ordered her to heal Fintan’s mind so they can get information about the rebels and their plans. Fintan is one of the leaders of the Neverseen, the group of rebels who intend to take down the council. Their actions were responsible for Sophie’s kidnapping and the fires that killed both elves and humans. Sophie reluctantly agrees to do the healing.
Sophie returns to her adoptive parents, Grady and Edaline, and sees Edaline cleaning out Jolie’s room. Jolie, the couple’s daughter, died 16 years earlier in a fire started by a pyrokinetic working with the Neverseen. Jolie’s fiance, Brant, was badly burned in the fire. Though he escaped with his life, he never recovered from his grief and guilt over not being able to save Jolie. He lives in a small house far away from others where Grady and Edaline care for him. Sophie has suspects that Jolie used to work for the Black Swan. So Sophie offers to pack up Jolie’s belongings so she can search for clues.
On the first day back at school, Sophie is surprised to learn that the classified plans for her to heal Fintan have been leaked. She is faced with students who are angry and fearful that she has agreed to heal an incredibly dangerous criminal. Sophie’s tutors help her to prepare for the healing and ask her to choose someone to assist her with Fintan. She chooses her friend Fitz, Alden’s son. She and Fitz work on trust exercises and develop support strategies for when she goes into Fintan’s mind.
In a session with another tutor, Lady Cadence finds a substance called aromark all over Sophie and Keefe. The substance was placed on Silveny’s tracker and is used by the ogres as a homing device. All the ogres’ weapons use aromark as their targeting system. Sophie, Keefe, Alden and anyone who touched the tracker needs to have the aromark purged from their skin.
Before the healing, Grady tells Sophie that Fintan may know the identity of the pyrokinetic who set the fire that killed Jolie, as the man was Fintan’s protégé. Sophie and the other elven councilors travel to an elaborate prison for Fintan’s healing, but the procedure goes horribly wrong. Sophie goes into Fintan’s mind and sees memories of the pyrokinetic. Before she sees his face, Fintan gains consciousness and starts an everblaze, a fire so intense that it burns everything and can only be extinguished by a substance called frissyn.
Sophie and Fitz barely escape the prison before it burns, and they are quickly sent to collect ingredients for the frissyn. The fire burns a portion of the city of Eternalia before it is put out. Afterward, Sophie and Fitz learn that Councilor Kenric was killed in the fire. Kenric was always kind to Sophie. She is heartbroken and feels responsible for his death.
At Kenric’s memorial service, the crowd is openly hostile toward Sophie, blaming her for his death. Before the service ends, the king of the ogres, Dimitar, arrives under the guise of paying his respects. Sophie believes the ogres are working with the Neverseen. She decides to use her telepathic abilities to read Dimitar’s mind without his knowledge or permission, a highly illegal act. Dimitar instantly detects Sophie’s intrusion, a violation of the Elvin-Ogre Peace Treaty, and demands that she be punished or her actions be considered an act of war.
Sophie is taken home and must wait several days until a new councilor is elected to know her punishment. The Black Swan contacts Sophie and gives her instructions for a meeting. Sophie, Keefe and her bodyguard, Sandor, use light-leaping to go to a series of obscure places before finding themselves on an abandoned beach.
Three figures rush from the water to attack them but are intercepted by dwarves. The figures escape. Sophie learns that the Black Swan was using her and her friends as bait to draw out the Neverseen. Sophie demands a real meeting with the Black Swan and gets it a short time later.
Mr. Forkle meets them in the human world, in San Francisco, outside Sophie’s old home. He tells her that the Black Swan had to be careful because information was being leaked. The Neverseen has been following Sophie and Keefe by using the aromark on Keefe’s family pin, the one given to him by his father. While Keefe has a poor relationship with his parents, he is devastated that his father is a traitor and a rebel. Keefe agrees to help the Black Swan stop his father and the Neverseen.
A new councilor is elected and announces that members of the Black Swan will be tracked down and punished for their illegal actions. While some protest that they are going after the wrong group, Sophie’s punishment is also publicly handed down. A device made by Sophie’s friend Dex, a technopath, is placed on her head to restrict all her abilities. The device causes Sophie intense pain.
Dex is horrified that his invention will be used in this way. He wants to remove the device, but Sophie fears he will be exiled if he removes it. She is distraught when she returns home. For three days she takes sedatives so she will not have to be awake and face her harsh, powerless reality.
Her friends Keefe, Fitz and his sister, Biana, eventually find a way to cheer her. The Black Swan plans a trap to draw out and apprehend members of the Neverseen. Sophie decides to continue investigating Jolie’s death.
Sophie finds a coded journal in Jolie’s room and painstakingly deciphers it to learn the shocking truth. Both the Black Swan and the Neverseen recruited her. She joined the Black Swan as an operative and the Neverseen as a spy. She learns that Brant wasn’t talentless. He was secretly a pyrokinetic, and Fintan was training him. When Jolie tried to reason with him, he started the fire that killed her. Sophie also realizes that Brant was her kidnapper.
Sophie tells Grady of Brant’s betrayal. He gets extremely angry and teleports, but Sophie grabs onto him so she can follow him to Brant’s house. Brant is waiting for them, no longer pretending to have a broken mind.
He and Grady fight. Brant calls an everblaze. Grady uses compulsion to make Brant burn off his own hand. Grady wants to kill Brant, but Sophie stops him. When it seems that Brant will burn them both, Sophie uses her device to call Dex, who arrives and punches Brant.
Brant escapes after telling them that the Neverseen knows about the trap the Black Swan has set, and they are prepared. Sophie asks Dex to take Grady to a physician. He leaves after taking off her ability restrictor.
Sophie teleports to Mount Everest in time to warn her friends that the Neverseen know about the trap. Before the fight starts, Mr. Forkle gives Fitz some important information. Sophie, Fitz, Biana, Keefe and Sandor fight the Neverseen rebels. Keefe finds out the traitor isn’t his father. It’s his mother, Lady Gisela.
Keefe confronts her, she fights Biana, and right before she is captured, Lady Gisela throws herself off a cliff and teleports. Mr. Forkle captures one of the other rebels and takes him in for questioning. Mr. Forkle also tells Sophie that the next step is hers; she has a choice to make.
The children and Sandor, who was badly hurt in the fight, return to Everglen. At Alden’s house, Sophie decides to join the Black Swan. Her friends want to go with her, but she is reluctant to put them in danger.
With the threat of exile from the councilors looming over them for helping the Black Swan, their parents agree that it is best for them to join. Fitz reveals that their destination is the city of Florence in the human world. Sophie, Keefe, Fitz, Biana and Dex prepare to leave for Italy.