Raising kids is tough. Keeping them alive as the zombie apocalypse begins is tougher. But that's exactly what stay-at-home mom Karen needs to do: fight fiercely to keep her young daughters safe as her husband Jim battles his way across the city, so they can escape the carnage together. On the worst day of her life, Karen finds that she will do anything to protect her family, and that the line between life and death has teeth.