By foot across the galaxy: Walkers transport starships across interstellar space, but their abilities are rare. Few people have the mental talents to control the weird quantum technology that powers a star-drive. When a mysterious force disables the two Walkers on board the Xinglong Hao, novice Walker Gillian Berry is thrust into the role before her training is complete. Several thousand passengers now depend on her. But she is becoming distracted by alien thoughts and urges that she can't understand.