After an attack renders her blind, Ellen Ashland (Madelaine Petsch) withdraws from the world to recover in a high-rise apartment. But soon she plunges into paranoia, unable to convince anyone of a certainty that shreds her sanity; her assailant has returned to menace her by hiding in plain sight. Ellen must grapple with her newly unreliable senses if she is to uncover a plot against her. But once she reveals the shocking extent to which her enemy deceives her, she stands to lose not just her sight, but her life.