In a small college town in northern California, a lonely young man is working himself to the bone to solve a sixty-year-old problem … a stranger with a will of iron and eyes the color of ice is searching for someone he can't identify … and a girl who loves plants is about to grow roots of her own. When Cara Gallagher’s parents are transferred overseas again, she’s off to spend her senior year of high school living with her sister, a graduate student at the famed McNair University. Cara, a girl with a passion for science and an indifference to people, hopes this move will be her first step in claiming the independence she craves. Cara has her future planned down to the letter: her college, her major, her career. Then she saves Will Mallory’s life, and both of their futures are completely rewritten. The last years of Will's life have been spent shifting from one identity to the next, dodging the FBI, and trying desperately to find a way home. But Will's home is forty-four light years away, and to reach it he'll have to outwit the man who's hunting him—and leave behind the only love he's ever known.