Tamora Pierce focuses on Tris, the merchant's daughter with a talent for literally stirring up the weather, in Circle of Magic: Tris's Book.

A couple of months have passed since the earthquake that rocked Winding Circle Temple and bonded the four young mages, and repairs to the damage are still underway when the sleepy summer calm is shattered by mysterious explosions.

Mage Niko Goldeneye, Tris's teacher, calls upon her to help him focus her magic so that he can find out the cause of the explosion, but although they are able to call up images of the actual event, they still don't know what happened. Then, while out repairing security nets with her teacher, Frostpine, Daja spots something strange in the harbor: she senses a boat but cannot see it when she looks directly at the place where it should be. She combines her magic with Frostpine's, and together they see the boat for what it is: a pirate's scout ship. The harbor is full of magically masked pirate ships led by pirate queen Pahua, and Winding Circle Temple, with its defenses weakened by the earthquake, is her target.

If that isn't enough, she and her mage brother Enahar have a new and terrible weapon: exploding stones launched from catapults with which they bombard the Temple, further weakening the defenses. Not only is there death and damage, but the people of the Temple are becoming both fatigued and demoralized.

Tris finds that when she is frightened or angry, she can summon up even more powerful magic and deflect or destroy the stones. Barred from helping the adults fight the pirates, her friends try to help her learn how to consciously control her power. Control doesn't come easily to the girl, full of anger and resentment at being shunned and rejected by her own family. Not even a visit from the only cousin who was ever kind to her helps, especially when he doesn't appear to be all that he should be.

Her anger spurs her to try to stop the pirates herself, but her friends persuade her to let them help. When her pride born of anger nearly destroys herself and her friends, she realizes that she is no better than Enahar unless she exerts control.

Pierce creates a fascinating portrait in Tris, who is surrounded by tiny lightning bolts when she is angry, a neat image. Tris is prickly and angry but also very vulnerable, and the development of her personality is convincing. She matures in her understanding, but her growth is natural and she recognizes that she still has a long way to go. Pierce's fast-paced and exciting plot also doesn't pull any punches: likable characters are injured or killed and Pierce forces the characters and the reader to face the realities of warfare on any scale.

A fine follow-up to Circle of Magic: Sandry's Book, Circle of Magic: Tris's Book will more than whet young readers' appetites for the next book in the series.