The following version of the book was used to create this study guide: Sutherland, Tui, Wings of Fire Book 10; Darkness of Dragons. Scholastic Press, New York, NY, 2017. Kindle AZW file.

Qibli is a SandWing dragon who attends school at Jade Mountain Academy. The goal of the school is to create an environment that encourages understanding between the seven tribes of Pyrrhia. Qibli has become close friends with several other dragons: a RainWing named Kinkajou, a SeaWing named Turtle, an IceWing named Winter, and a NightWing named Moon. Qibli tends to be fiercely loyal to his friends, countered only by his devotion to Thorn, recently crowned queen of the SandWings. Qibli remained behind while Turtle and Moon traveled to the Rainforest, then on to the lost kingdom of the NightWings. Qibli worries about them because an ancient, huge, and magical NightWing named Darkstalker has recently escaped from a spell that kept him bound inside Jade Mountain for 2,000 years. Darkstalker has enchanted almost everyone he encounters. So, they trust and like him, but Qibli's instincts lead him to seek protection. Turtle, who also has animus (magic) powers, made an earring that protects Qibli from Darkstalker's magic. Qibli uses a magic bowl to multiply his earrings and begins passing those out to every dragon around while considering how he might eventually try to defeat Darkstalker.

Meanwhile, Qibli discovers two SandWing students – Onyx and Ostrich – have disappeared from the school. Feeling a sense of responsibility, Qibli is forced to face his past as he follows them to the Scorpion Den, a lawless town in the SandWings' kingdom. There, Qibli is beset by memories of his cruel mother, siblings, and grandfather. His mother claims to have been imprisoned ever since Qibli left her years earlier and Qibli makes it seem he is accepting her help to escape from the Scorpion Den. They fly to the SandWings' palace where Qibli provides Thorn with information, then directs her to arrest his mother. It is quickly clear she was using Qibli to get close enough to try to kill Thorn. Qibli's grandfather, Vulture, arrives at the palace with Onyx, the long-lost daughter of Prince Smolder, and Qibli is terrified for Thorn until Thorn helps him realize that she is a worthy queen capable of retaining her crown.

Qibli receives an enchanted message from Turtle pleading for help, and he encounters Turtle's sister, Anemone, on the way. Qibli's magic earrings release Anemone from Darkstalker's spells. She joins forces, leading the way into the Night Kingdom even though they are not certain how to stop the invincible and evil Darkstalker. He is unable to understand that the world has changed while he was under the spell. He continues to harbor old grudges against IceWings who are no longer living. He launches a battle between the IceWings and NightWings, though Qibli helps bring that to an end. Darkstalker continues to try to manipulate others into liking him, and he offers to make Qibli into an animus dragon, promising they can then rule the country together. Qibli sees the danger and the flaws in that, including that Darkstalker is not trustworthy.

Darkstalker is shocked when his mother, Foeslayer, reveals herself. Foeslayer has been under an enchantment for most of the the past 2,000 years, meaning she has barely aged. She looks back on her life and realizes she could have done more to give Darkstalker a happy life. She offers that now, encouraging him to give up his power and start his life over, as a dragonet with no memories of being Darkstalker. He refuses, but Kinkajou has a scrap of magic paper and enchants a strawberry to change Darkstalker's life. Foeslayer chooses the name Peacekeeper for him and Hope for herself. They settle into life among the NightWings living happily in the Rainforest.