Prince Arctic of the IceWings feels trapped by his tribe’s strict rules. His mother, Queen Diamond, is especially hard on him because he has animus powers. IceWing rules dictate that animus dragons can only use their magic once to make a special gift for the tribe, and Arctic struggles to decide what he can create.

Snowflake, a noble dragon whom Queen Diamond wants Arctic to marry, tells Arctic that the NightWing delegation has arrived. The two of them go to greet the delegation, but outside the guest quarters, they meet a young NightWing named Foeslayer. She chats easily about the cold and the sunset, annoying Snowflake but catching Arctic’s attention.

Snowflake leaves, and Arctic continues talking with Foeslayer. He becomes enchanted by her boldness and warmth. Breaking his tribe’s rules, he uses his animus magic to enchant one of his earrings to keep her warm and safe from danger. Foeslayer asks if Arctic is worried about losing his soul, and he tells her that his soul belongs to her. They hold talons, knowing that both of their tribes would never accept them. Foeslayer says that she feels like the world is about to change.

Fathom, a two-year-old SeaWing who is a minor prince in the kingdom, lines up on the beach with seven other young dragons for a special test. His best friend, Indigo, is also taking the test but tries to distract him, and his sister, Pearl, scolds them just before Queen Lagoon arrives. Albatross, who is Fathom and Pearl’s grandfather and the SeaWing’s only animus, surfaces from the ocean.

Albatross does not like testing young dragons for animus power, but Queen Lagoon orders him to do it. He hands out coconuts and tells the dragonets to whisper a command to them. Fathom politely tells his coconut to hit Albatross, but nothing happens. Indigo tells him to be more forceful. When Fathom shouts the command, the coconut hits Albatross.

Everyone is shocked, and Pearl announces that Fathom is the one who did it. Fathom feels excited and scared. He is happy to be special but also nervous about the danger of animus magic. As he watches, a vine suddenly strangles a seagull nearby, reminding him of how serious this magic is. Albatross states that he is pleased to have another animus in the family, but Fathom wonders if he is lying.

Inside his egg, Darkstalker listens to his parents argue. His mother, Foeslayer, wants the eggs to hatch under the full moons, while his father, Arctic, wants to return them to the Ice Kingdom. Foeslayer points out that Queen Diamond would kill the dragonets, and Darkstalker feels Arctic’s rage. Darkstalker can already feel their emotions—his mother’s love and his father’s anger.

As the light of the three full moons shines down, Darkstalker breaks out of his egg and feels power flow into him. He sees his parents for the first time and immediately loves Foeslayer. Arctic, on the other hand, feels dangerous and cold to him. Darkstalker understands that Arctic loves Foeslayer but nothing else.

Foeslayer gives Darkstalker his name, and Arctic protests. Foeslayer says that he can name the other dragon, though she does not believe the second egg will hatch. Darkstalker knows it will and that the dragon inside is his sister. He has a vision in which he helps her hatch under the full moons and they share their powers. However, he decides not to help. Darkstalker wants the full power and his mother’s love all to himself. He watches a thousand possible futures disappear as he makes his choice.

Albatross sends for Fathom, but Fathom does not want to go to him without Indigo. Indigo’s mother died when she was young, and Fathom’s mother, Manta, helped raise her. Pearl and Indigo convince him to go by himself.

On the beach, Albatross jokes with Fathom and then takes him to a secret island. There, Fathom sees a strange stone palace growing from the ground. Albatross explains that he has been building it with animus magic for seven years. Fathom finds the palace creepy and wonders how it knows when to stop growing.

Albatross shows him the blueprints and asks if Fathom has any ideas. Fathom suggests adding plants to hide the palace from flying dragons. Albatross likes this idea.

He then warns Fathom about how dangerous animus magic is. He shares the story of how he discovered his powers. When he was young, his sister Sapphire teased him and took a shell that he was playing with. In a moment of anger, he told the shell to bite off her claws—and it did. Because of that, Sapphire lost her right to be queen and lost her ability to think rationally. She now lives alone on an island.

Albatross tells Fathom never to use magic alone and to ask his permission first. Just as they begin their lesson, Indigo appears. She says that she followed them because she was worried. Albatross ends the lesson, and they head back.

Fathom enchants a piece of wood to cheer up Indigo, who worries that Queen Lagoon will be angry at her. It turns into a wooden octopus, which then comes to life. The octopus, named Blob, hugs Indigo. Fathom feels proud that his magic could make her happy.

Clearsight is a NightWing who has powerful visions of the future. She spends her time in the library, writing down possible timelines and trying to find the best paths for future actions. Her father worries that she is too young to carry such a burden. Clearsight ignores him, haunted by visions of death in the Kingdom of the Sea.

She also worries about a dragon named Darkstalker. In some futures, he is dangerous. She wonders if it would be better to never meet him.

Her father tells her that she must attend the NightWing school. Clearsight refuses at first, saying that she needs more time to study the futures. Eventually, her father agrees that she can attend the following year, but he says they cannot delay much longer because Queen Vigilance wants all seers trained.

Clearsight is nervous about meeting Darkstalker, who also sees the future. She fears what might happen when two powerful seers with intertwined fates cross paths.