Silver Moons, Black Steel, Harper Tara

But she cannot elude those who seek her: the Gray Ones, who grow restless with her absence; the brother searching the wilderness for his Wolfwalker twin; and the people of her homeland, who are relying on her to secure their future with her new knowledge. And there is one other: a distant warrior unable to resist the mysterious force that summons him to find a woman whose face he has never seen, whose name he has never heard.