Lyric Walker's life forever changes the night she witnesses the arrival of the Alpha, a five-nation race of ocean-dwelling warriors. The world's initial wonder and awe over the Alpha quickly turn into paranoia and fear, transforming her hometown of Coney Island into a military zone with violence bubbling just beneath the surface. Despite her best efforts, Lyric is thrust into the middle of this clash of civilizations when the Alpha teenagers are forced into her high school and she is recruited to help their crown prince, a battle-scarred boy named Fathom, adjust to life as an American teenager. Fathom is full of anger, and violence follows him everywhere, yet she finds herself drawn to him. Their love, however, is a dangerous one, with forces on both sides working to keep them apart, and it threatens to expose a shocking secret Lyric and her family have been keeping since she was a baby. And while the world sees the Alpha as an invading army, Lyric discovers that they are in fact humanity's only hope of survival, because there's something much more terrifying than the Alpha. And it's on its way.