Struggling after a recent family tragedy, teenager Emma Drakeford begins a video documentary about her life for a school project. Her life is turned upside down as a terrifying virus sweeps through her small town, turning her friends and neighbours into vicious monsters. Quarantined with her family, Emma believes they are out of harm’s way but when the contagion finally infiltrates their home Emma and her family are faced with an impossible decision – if someone you love becomes a threat, do you kill them in cold blood or save them at the risk of your own life?