Thomas, who’s built a strong reputation in historical romance, turns to YA fantasy with aplomb in the first installment of the Elemental Trilogy. Sixteen-year-old Iolanthe Seabourne is an elemental mage with a gift for fire; she has trained in obscurity with her drug-addicted mentor for as long as she can recall. When their quiet life suddenly turns to chaos, he’s coherent enough to help fling her out of danger but into a world she does not know—late 19th century London, a “nonmage” society that coexists with the rival mage realms of Atlantis and the Domain. Rescued by the Domain’s young master, Titus Elberon, and disguised as a boy attending Eton College, Iolanthe has to learn who and what to believe. Titus will do anything to overthrow Atlantis; Iolanthe dreams of becoming a mage scholar. Only one of them knows that death is imminent. As expected, Thomas’s romantic touch is sure, but she is just as adept with fantasy world-building, carrying the banners of Anne McCaffrey and Caroline Stevermer, among others, in a wonderfully satisfying magical saga. Ages 14–up. Agent: Kristin Nelson, Nelson Literary Agency. (Sept.)