Soren's sister, Eglantine, has fallen under a strange spell. She has vivid dreams of seeing her mum in the Beaks, though this is not possible because her mum is dead.
Her best friend, Primrose, is worried about Eglantine's condition. She senses that although Eglantine's condition is worsening, she also feels that something inside her is weakening. Also, she is disturbed that Eglantine spends too much time with Ginger, another Barn Owl who once was a Pure One but now says that she would rather live at the Tree.
One night, Eglantine and Ginger fly over the Sea of Hoolemere and to the Beaks, where Eglantine meets her "mother."
Eglantine notices that her mother is not quite her mother. For example, her mother's face was never so big and white before and calls Eglantine "darling" something that Eglantine knows that her mother never calls her. Despite all this, Eglantine is convinced that this owl is her mother and basks in her love.
Eglantine visits her "mother" several times but odd things happen. For instance, she can never remember getting back to the tree and wondered why her dad was never there.
Primrose decides to follow Eglantine one night and is captured by a Sooty Owl. She realizes that the Pure Ones have learned to shatter. Shattering is the process of destroying one's will by the use of flecks. The gizzard becomes still and the owl's mind will be incapable of sorting out thoughts. She realizes also that the Pure Ones had shattered Eglantine.
Meanwhile, Eglantine is reassembling the shattered fragments of her mind. She begins to doubt that the owl is really her mother and flies back one last time to find out if the owl is her mother.
Eglantine finally realizes that the owl that she had called "Mum" was in fact her brother's mate, Nyra. Eglantine and Primrose are held prisoner by the Pure Ones. Eglantine steals Nyra's egg and she escapes with Primrose into the forest fire.
Soren along with a group of owls are planning how to rescue the two fleeing owls. They are shocked to find out that they are horribly outnumbered until the intelligent Ezylryb suggests a brilliant "feint" plan with the usage the language of the Northern Kingdoms.
The Guardians clash with the Nyra Annihilators and manage to drive them off. Eglantine drops the egg and it breaks.
The Guardians later learn that the Pure Ones have taken over St. Aggies Academy and they charge Soren and the chaw of chaws to go on a mission to the Northern Kingdoms, where they hope to find military aid.
The review of this Book prepared by Jenny