Darius Acrux teleports himself, Lance Orion, and the Vega twins—whom he calls Roxy (Tory) and Gwendalina (Darcy)—from the cliff to King’s Hollow, the Heirs’ private treehouse sanctuary, immediately following their traumatic encounter with his father, Lionel. Darcy confronts Darius, while Tory reveals that she and her sister remember everything despite his attempt to use Dark Coercion to erase their memories of the ritual. Their newly Emerged Order—or unlocked power—lets them resist psychological manipulation. Darius is shocked, as he’s never been able to resist his father’s dark magic himself.

When Darius embraces Tory in relief, she blasts him across the room with her power. She acknowledges he tried to save them but still blames him for his ultimate failure. Orion reveals that Lionel mistook their Order forms, or the creature with which their elemental powers are aligned. They are Phoenixes, a powerful Order unseen for over a thousand years. They will keep this secret, as Lionel would eliminate the twins if he discovered their true power, which threatens his position.

As a result of the ritual, wherein the twins were used as a conduit to transmit shadow magic to Lionel, Darius feels the shadows living beneath his skin as a permanent presence. Orion tells the twins he believes the shadows only took root in him and Darius. Roxy refuses to speak with Darius privately and threatens him, though he secretly maintains his feelings for her.

Orion leads Darcy and Tory to a bedroom in King’s Hollow. After Tory uses the bathroom, he kisses Darcy briefly, apologizes for the night’s events, and leaves. In bed, the sisters hold hands for comfort. Tory doesn’t blame Darius for choosing to save his brother Xavier but resents him for being too much like his father. As she expresses her anger, Darcy feels darkness and hatred. When Tory notices Darcy’s eyes have gone dark with shadows, they realize the shadows from the ritual have taken root inside them as well. Darcy wants to tell Orion, but Tory refuses, not trusting him to keep it from Darius. They agree to keep the secret for now.

The next morning, Darcy finds Orion making coffee. Darius returns from flying in his Dragon form, frustrated. Tory announces they’re leaving, and Orion promises Darcy he’ll research Phoenixes. As the sisters walk through The Wailing Wood, Darcy worries about the shadows inside them.

Max Rigel, a Siren, wakes beside Geraldine Grus, a friend and classmate of Tory and Darcy, after sleeping with her during the Lunar Eclipse. He reflects that she was immune to his emotion-boosting abilities, making their encounter more rewarding than usual. When he attempts to initiate more intimacy, Geraldine stops him, explaining she needs to leave for breakfast. She dismisses their night together as motivated by the celestial event, implying she’s embarrassed by having slept with an Heir. When the enamored Max protests, Geraldine insists their hookup will not happen again and leaves. Confused, he resolves to pursue her.

The morning after the Eclipse, Orion finds Darius brooding over Tory. Needing blood, Orion feeds from Darius, which activates the Guardian Bond that Lionel cast on them, which forces him to protect Darius. Orion resents how it muddies his feelings. He tells Darius they must protect the Vega twins, though Darius admits the twins are a threat to his throne. Orion mentions his mother, Stella, will likely help Lionel master the shadows.

Orion travels to the secret archives beneath Venus Library to research Phoenixes. That evening, he meets with Darius and the twins in his office. As he begins explaining his findings—that Phoenixes are highly resistant to psychological magic and regenerate power from fire—a black-winged figure appears at the window. Gabriel Nox, the new Tarot teacher and Orion’s Nebula Ally (a fated friend whose soul is bound to his), reveals he had a vision of the twins as Phoenixes. Though Darius objects to involving another person, Orion arranges for Gabriel to tutor the twins in secret so they can avoid Order Enhancement classes where their true nature might be discovered. Orion continues that Phoenix fire can harm even Dragons, a fact Tory uses to taunt Darius. Internally, Orion considers convincing Darius to share the throne with the Vega twins.

On the first day of classes after The Reckoning, a series of school trials, Tory wakes from a nightmare where a woman’s voice called to her. She’s been drinking to cope with having the shadows inside her. Outside The Orb, or the mess hall, Caleb Altair surprises her. When she grows angry, the shadows cross her vision, which he notices. Tory admits the Eclipse pushed her toward Darius and that she likely would have slept with him if her Order hadn’t Emerged. Caleb asks her to be exclusive, but she refuses, wanting to keep their relationship casual. Darius interrupts, warning Caleb that Tory might accidentally set him on fire during sex due to her new Order.

At breakfast, Geraldine entertains the group with the story of her one-night stand with Max, publicly rejecting his advances when he approaches. Tory arrives late to Professor Gabriel Nox’s Tarot class. When Kylie Major tries to get her into trouble, Nox instead penalizes Kylie’s house. Tory notices he has the silver ring marking an Elysian Mate, his fated one true love. Under a silencing bubble, Nox shows the twins a Tarot card he received from someone called Falling Star with a message directing him to them. The twins reveal they’ve been receiving similar cards from Falling Star, whom they identify as their murdered mentor, Professor Astrum. Gabriel has a brief vision upon hearing this. The three agree to work together secretly to uncover the cards’ meaning.

In Cardinal Magic class, Orion announces that the deadline for club sign-ups has passed. Darcy and Tory are the only students who missed it. Orion assigns Tory to the cheerleading squad and Darcy to the brutal Pitball team, shocking her. When Kylie Major taunts Tory, Orion uses magic to knock Kylie from her chair. The lesson covers creating Silencing Bubbles. While practicing blocking external sound, Darcy hears a faint, whispering voice and experiences overwhelming bliss before fainting. She wakes with Orion and Tory over her. She lies that she accidentally cut off her air supply, but Orion appears suspicious. Diego Polaris, a student with whom the Vegas have been in conflict before, watches with alarm from across the room.

That evening, Darcy brings Tory to her meeting with Orion. They find him with wine. When they describe the shadows inside them and the female voice they’re hearing, Orion speculates that souls trapped in the shadows can now connect directly to them. He decrees they must join his and Darius’s secret dark magic lessons, and Tory reluctantly agrees. After Tory leaves, Orion kisses Darcy. He gives her a rose quartz crystal, explaining it’s a Solarian tradition signifying a desire for exclusivity. Darcy accepts. He then shows her a hidden library in his office filled with his old Pitball trophies and a photo of him in school. She can tell he used to be happier than he is now.

Tory and Darcy attend their first dark magic lesson with Orion and Darius. Tory is apprehensive, remembering past trauma at this location, but she needs the lesson because the shadows and her nightmares are worsening. After arguing with the men, Darcy convinces Tory to be civil despite her frustration with Darius.

Inside a hidden cave, Orion explains they must practice letting the shadows in while using an anchor with a strong emotional bond to pull themselves back. Tory insists she and Darcy serve as each other’s anchors and volunteers to go first. Tory allows the shadows to flood her body, experiencing intense euphoria. She successfully summons shadow magic, but the power amplifies her anger toward Darius. A voice urges her to get revenge for hurting her. Darcy’s voice breaks through, and Tory banishes the magic before collapsing. Shaken, she tells Darius the shadows wanted her to kill him. As they prepare for Darcy’s turn, Tory reflects on how she enjoyed wielding that power, shaken.