This is an excellent follow-on book. The things we learned about the protagonist and her world are used in this book and new things are added. Thea turns out to have a gift for cybermagic -- making magic using computers -- and at first she's thought to be the only one. But then spellspams start coming and when you open one, you get hit with the spam, so there must be another. But who? The initial spellspams were just pranks, but they became more involved and more likely to hurt people as they went on.
Thea and her computer-expert friend go to a special mage's house to help find the spellspams and for him to help develop Thea's gift. It was the right place to go, but the wrong reasons. Thea has to push herself to the limit to keep our world safe from the Alphiri and her friends, family, and other mages help.
Again, a quick-reading tale that keeps you up late. Highly recommended for all.