Perilous Sea, The (Book 2 Of The Elemental Trilogy)

Description:
Iolanthe and Titus continue their mission to defeat the Bane in this striking sequel to The Burning Sky—perfect for fans of Cinda Williams Chima and Kristin Cashore—which Publishers Weekly called "a wonderfully satisfying magical saga" in a starred review and Kirkus Reviews said "bids fair to be the next big epic fantasy success."
After spending the summer away from each other, Titus and Iolanthe (still disguised as Archer Fairfax) are eager to return to Eton College to resume their training to fight the Bane. Although no longer bound to Titus by blood oath, Iolanthe is more committed than ever to fulfilling her destiny—especially with the agents of Atlantis quickly closing in.
Soon after arriving at school, though, Titus makes a shocking discovery, one that throws into question everything he believed about their mission. Faced with this revelation, Iolanthe struggles to come to terms with her new role, while Titus must choose between following his mother's prophecies—or forging a divergent path to an unknowable future.