Chapter 1: A Wayward Crow
While hunting, Sigrid Henderson comes across Velius Flynn and his Changewing, Shimmer and Speed Stinger Milo before he own dragons - Stormfront the Skrill and Smog the Smothering Smokebreath - arrive to the confrontation. Though cautious, once realizing that Velius is not allied with the Stormchasers, Sigrid relaxes and the two ultimately form the partnership they now have.
Chapter 2: Cover of Nightfall
In need of supplies and new tools, the Night Riders arrive at Berk, where, as far as they know, the Vikings still kill dragons. So, Sigrid and Shimmer sneak into the village but are discovered. Sigrid is injured by Hiccup, who convinces the group that they are not hostile to dragons.
Chapter 3: Academy Tour
After Sigrid's wound is treated, Hiccup and Astrid treat Sigrid and Flynn to a tour of Berk and their Dragon Academy while they learn about the pair's dragons. Elsewhere, Dagur the Deranged learns of a Skrill rider on Berk.
Chapter 4: Berserker Attack
While the Berserkers attack Berk to claim Sigrid's Skrill, things only get worse when Baldr Armstrong, Sigrid's fiance and Stormfront's original intended rider, finally catch up to them. Sigrid quickly devises a plan and manages to get Baldr and Dagur to fight each other while she and Flynn escape Berk.
Chapter 5: Captured!
Sigrid and Stormfront are recaptured by Baldr and taken back to Stormchaser Island. Smog informs Flynn of this as they set off to rescue their friends.
Chapter 6: Shimmer of Hope
While Sigrid is being forced to marry Baldr, Flynn successfully sneaks onto Stormchaser Island and frees Stormfront while Shimmer and Milo rescue Sigrid. During the chaos, Sigrid's father falls to his death, too stubborn to accept Sigrid's help. Baldr wounds Shimmer and Flynn accidentally shoots Baldr with his crossbow. Though the group escapes, Shimmer succumbs to her wounds and dies.
Chapter 7: Good Fortune
Heartbroken over the loss of his dragon, Flynn returns to the Haven with Sigrid. The Tinkerers embrace dragons and elect Sigrid the headmaster of their new dragon academy. Flynn meanwhile, chooses to bury Shimmer where they first met. Weeks pass as Flynn continues to mourn Shimmer before Sigrid finally convinces him to come out. In his satchel, the pair discover a Stone of Good Fortune, which turns out to be a Changewing egg that explosively hatches. Flynn realizes that Shimmer had laid an egg prior to her death and he names the newborn hatchling Fortuna.
Chapter 8: New Arrivals
Stormfront has disappeared, causing Sigrid to worry. In order to distract herself, she decides to teach Flynn traditional archery, though with little success. During the lesson, Flynn confesses his feelings for Sigrid and she reciprocates. A few days later, Stormfront returns with his eggs in tow. Sigrid and Flynn realize that Stormfront did not want to abandon his eggs like he had been abandoned by his parents.
Chapter 9: For the Dancing and the Dreaming
Stormfront's eggs hatch into five baby Skrills that Sigrid names Stormchaser, Firebolt, Raincatcher, Heavy Wind and Skyscorcher. As Sigrid and Flynn continue to grow closer, Flynn ultimately proposes to her and she accepts. Stormfront gives her away at their wedding and some time later, they have triplets: Sigurd, Frænir, and Alva.