Seventeen-year-old Tia Scott has led a relatively typical life, aside from the tragic loss of her older sister in a hit-and-run accident. Her world takes a bizarre turn when she begins to show unusual symptoms and discovers she’s been infected with a virus that gradually transforms her into a zombie. In her urgent quest for a remedy, she places her trust in Flynn, a solitary classmate who claims to be an authority on the paranormal. Tia’s situation worsens when a friend of her boyfriend, Connor, is killed. She suspects Connor’s friend Jason is involved, but reporting to the police would put her in danger. With time running out before her condition becomes irreversible, Tia seeks assistance from her mother, Kate, and a withdrawn doctor, hoping they can halt the virus before Jason learns she’s the informant.