Premise
In the nation of Aeland, magic is stigmatized. Witches are considered mentally ill. If they are identified and convicted, they are sent to asylums. Unbeknownst to the general public, the country's climate is only sustainable because of magic. The Queen's Invisibles, a group of wealthy mages, work to maintain the climate. Mages with the ability of "storm singing" are highly valued; those with other abilities are not. Mages who cannot sing storms are classified as "secondaries"; they are enslaved and used as magical batteries by their storm singers.
Christopher Hensley Jr. is a mage with the gift of healing. His sister Grace is a storm singer. Christopher flees from his fate as a secondary. He changes his name to Miles Singer and becomes a physician. Aeland and the neighboring nation of Laneer go to war. Miles joins the armed forces and later becomes a psychiatrist at a veterans’ hospital.
Plot summary
One night, Sir Tristan Hunter brings a terminally ill man, Nick Elliot, to the hospital. Nick claims to have been poisoned. A dying Nick alludes to witchcraft; Dr. Miles Singer is unable to save him. Tristan reveals himself as an Amaranthine, a fae being. The Amaranthine are guardians of the Solace, the realm of souls. People who die in Aeland are no longer moving to the Solace, and the Amaranthine are investigating.
At a gala for hospital benefactors, Miles reunites with his sister Grace, who believed him to be dead. Miles was intended to be Grace's secondary before he ran away from his family. Grace promises to keep Miles's survival a secret from their father and asks to reconnect. Meanwhile, Miles and Tristan become lovers.
Miles investigates an illness affecting several veterans. They believe themselves to be possessed; several have gone mad and killed their families. Miles believes that Nick's death is somehow connected.
Grace betrays Miles's confidence to their father, Christopher Sr. Grace binds Miles as her secondary against his will. Grace promises to change the Invisibles so that secondaries are more respected, but refuses to release her brother.
Meanwhile, Miles and Tristan learn that Nick was investigating the witch asylums. Miles also learns that the Laneeri are the cause of the veterans’ madness. The veterans are being possessed by the souls of dead Laneeri soldiers.
Miles, Grace, and Tristan visit an asylum. There, they learn that the imprisoned witches are being used in a profane ritual. The souls of all who die in Aeland are being used to make aether, which powers the nation's technology. This explains why they are no longer moving to the afterlife. Christopher Sr. ordered Nick’s death when he discovered too much.
Miles, Grace, and Tristan attempt to destroy the aether production. Christopher Sr. arrives to stop them. Grace releases Miles from the binding spell, allowing him to cure the possessed veterans and destroy the aether production. Miles is injured after a confrontation with his father.
Miles awakens to find that he is being cared for by an Amaranthine physician. The Amaranthines, Laneeri, and Aelanders are on the verge of conflict as a result of Miles’s discovery. Miles hopes to work to navigate the new political situation. Tristan proposes marriage to Miles, who accepts.
