Riona's world shatters when her mother vanishes and her father's health crumbles, forcing her to abandon her teenage years and become the sole provider for her siblings. By day, she's a quiet nerd navigating Colton's High, but by night, she transforms into a lethal assassin—a trained killer with a singular purpose. Her double life remains carefully compartmentalized until Keith Anderson arrives at school, his persistent attention threatening to unravel everything she's worked to hide. As Keith grows obsessed with discovering the truth beneath her nerdy facade, Riona faces an impossible choice: protect her secret or risk letting someone past her carefully constructed walls. But in her world, knowledge can be deadly, and Keith's curiosity might make him her next target.