As 13-year-old Ava gradually loses her eyesight, she begins to feel herself completely new... It's supposed to be "the best summer" of her life, Ava's mother has promised her. But for Ava, the holidays begin with a shock: she will go blind. The fact that she can't see at dusk, at night, is just the beginning. Her retina dissolves. The radius of her field of vision will become tighter and tighter until it eventually closes. "I'm 13," she defiantly told the oculist, squinting her big brown eyes. But the disease has no regard for her youth.