The Demon's Covenant (The Demon's Lexicon Trilogy book 2) by Sarah Rees Brennan will be released on May 18, 2010 in the U.S.
Description: Mae has always thought of herself as in control, but in the last few weeks her life has radically changed. She’s learned that her brother Jamie has magical powers—and Gerald, the new leader of the Obsidian Circle, is trying to persuade Jamie to join the magicians. Even worse…Jamie hasn’t told Mae a thing about any of it. Mae turns to brothers Nick and Alan to help her rescue Jamie, but they are in danger from Gerald themselves because he wants to steal Nick’s powers. Will Mae be able to find a way to save them all from the power-hungry magician’s devious trap?