After a bloody battle, King Gaius now rules all three kingdoms of Mythica. With his mistress and adviser dead, Gaius turns to a powerful elder Watcher, Melenia, to find the Kindred.
The Kindred are four lost magical crystals that hold the purest essence of elemental magic: earth, fire, water and air. Melenia tells Gaius that if he follows her counsel, he will discover magic that will make him an immortal god who will rule over the entire world by her side. She tells Gaius that by building an imperial road through Mythica, he will find the Kindred in the Forbidden Mountains. The road is being built with slave labor from the poor people of Paelcia, with the help of Xanthus, an exiled Watcher with earth magic who works for Melenia.
Cleo, princess of Auranos and rightful heir to the throne, has been captured and forced to live in her own palace as a guest of King Gaius. Gaius breaks the engagement between Cleo and Lord Aron, betrothing her to his son, Prince Magnus instead. Gaius tells the people of Auranos that the union will unite Mythica. Neither Magnus nor Cleo want the engagement, but they cannot deny the king. Cleo still morns the death of the man she loved, Theon, whom Magnus killed, while Magnus is in love with his adopted sister, Lucia.
Lucia is a sorceress who used powerful magic to win the battle for her father; using all that magic left her in a coma. Secretly, her adopted mother, Queen Althea, has been feeding Lucia a potion to keep her unconscious. Gaius needs Lucia’s magic to find the Kindred, and Althea wants him to fail.
While she is unconscious, a Watcher named Alexius visits Lucia in her dreams. Through their interactions, they fall in love. Alexius tells Lucia that she will help restore the Sanctuary, the world of the Watchers, where magic has been fading since the Kindred were lost.
Jonas, a Paelsian rebel, has been recruiting more rebels to overthrow King Gaius. He and his friend Brion meet a Paelsian girl, Lysandra. Gaius' soldiers killed her family, and her brother has been missing since the raid on their village.
Queen Althea has been getting the sleeping potion for Lucia from a witch. On her way to get more, she is murdered. Gaius accuses Jonas of the murder, and the hunt for him intensifies.
While Cleo is getting fitted for her wedding dress, Jonas kidnaps her. He leaves a note for Gaius. In exchange for Cleo’s life, Jonas wants Gaius to stop construction on the road and free the enslaved Paelsians. Jonas doesn’t actually intend to hurt Cleo. He asks her to aid the rebel cause, and she agrees to help.
They plan to ambush the temple on her wedding day and kill Gaius and Magnus. Guards find the camp, and the rebels escape. Cleo pretends that she was truly being held against her will and that the soldiers are rescuing her from a harrowing ordeal.
The rebels attack the wedding ceremony, but Gaius, who anticipated the attack, had his own guards disguised as wedding guests. Most of the rebels are killed, and Jonas barely escapes with his life. Gaius suspects Cleo’s involvement and beats her before forcing her to continue with the wedding ceremony.
Cleo and Magnus are wed. At the wedding banquet, Prince Ashur of Kraeshia, a large kingdom across the sea, approaches Cleo. He asks her about legends of the Kindred. Cleo is purposely vague. After the banquet, Cleo and Magnus leave on a wedding tour.
In the Sanctuary, Alexius meets with Melenia, his elder. After the road is complete and the Kindred are found, Lucia’s blood will be spilled, and the Watchers will no longer be bound to the Sanctuary. Without the power of the sleeping potion, Lucia wakes up and feels a darkness stirring within her. Her father hires witches to teach her to use her power, but her ability far outpaces any teacher, and Lucia begins to enjoy the fear she evokes in others.
Magnus and Cleo’s wedding tour takes them to the castle in his homeland of Limeros. Cleo sees a large stone wheel in the garden. Legend says that these wheels were how Watchers had traveled between realms before the Kindred were lost. Cleo touches the wheel, and her ring, the one that belonged to the sorceress Eva and essential to controlling the Kindred, begins to glow.
At the end of the wedding tour, the couple returns to Auranos, but Magnus leaves soon after to hunt down his mother’s killer. Gaius has also tasked his son with checking on the progress of the imperial road. While camped out for the night, rebels sneak into the camp to steal weapons. Brion is caught and questioned. He refuses to answer, and when he denies that Jonas killed Queen Althea, Aron kills him.
Back at the castle, Nic asks Cleo to run away with him and confesses his love for her, but she refuses. Cleo tells Nic about the ring that once belonged to Eva and how she will use it to destroy King Gaius and take back her kingdom. Nic is upset about the rejection and leaves for a tavern to get drunk.
Prince Ashur finds him and questions Nic about the Kindred and Cleo’s magical ring. Nic denies knowing anything and flees the tavern. Nic drunkenly wanders the street until Ashur finds him. Nic fears Ashur will murder him, but the prince kisses him, and Nic responds positively to the kiss. Ashur is confident that the next time they meet, Nic will help him with the answers that he needs.
Magnus reaches the mountain camps where he will meet the imperial road’s engineer, Xanthus. After Magnus stops a drunken Aron from raping a girl, the two talk, and Aron confesses that he murdered Queen Althea because Gaius asked him to. Magnus intends to take Aron back to Auranos and confront his father, but Aron lunges at him, and Magnus kills Aron.
The rebels attack the road camp to avenge Brion’s death. Jonas is caught and stabbed in the heart, but a Watcher, Phaedra, takes human form and saves him with earth magic. Xanthus, Phaedra’s brother, finds them. Phaedra is overjoyed to see her brother, but Xanthus works for Melenia and he kills Phaedra. Jonas escapes, but Lysandra is captured.
In prison, Lysandra is reunited with her brother, Gregor. Before her death, Phaedra visited Gregor in dreams and told him that he and others like him can make a difference. She also told him that when Lucia’s blood is spilled and sacrifices made, the world will burn.
At the castle, Cleo suspects Lucia is the powerful sorceress who was prophesized. Cleo visits Lucia’s chambers and finds the girl heartbroken and sobbing. Lucia accidently killed her pet rabbit with her magic. Cleo comforts her, and her ring glows. Lucia feels calmer and more in control, and Cleo knows it is the ring’s power giving Lucia balance. Cleo offers Lucia friendship, and she accepts. Cleo believes that Lucia’s magic and the ring are the keys to destroying King Gaius.