Lewis (The Demon Queen
) throws cheerleading, higher mathematics, alternate dimensions, angels, demons and government agents into this satisfying and fun story. Ten-year-old Darby, a math prodigy, brings the other-dimensional Alpha Omega Function, also known as Bob, into the world. His 16-year-old sister, Livey, simply wants to pass math so that she can remain a cheerleader, and focus on her escalating crush on her class's student assistant. As Bob's obsession with order begins to get dangerous, both siblings find themselves forced to not only save the universe but to confront their own concerns with their parents' divorce. The lively cast of characters—which include the children's absentminded professor father, a mysterious young girl and a school bully—keeps the novel moving at a brisk pace, and Bob (who rarely stoops to pure malevolence) makes for a fascinating antagonist. Sadly, the climactic battle gets somewhat muddled, and the late addition of a key character throws off the pacing. Most readers should be able to forgive these flaws, as well as the too-pat emotional resolution, and enjoy the adventure and innovative use of math. Ages 12–up. (July)
