A lot can happen in 24 hours.A virus can kill a patient.A doctor can end up in quarantine.An outbreak can occur.And all hell can break loose.Still reeling from the loss of the patient who he had affectionately referred to as "Zero," Doctor Liam Alexander wakes up in quarantine, onlyto discover he'd been abandoned. With no explanation, he wanders into the hospital, only to discover a nightmare hell scape he'd never imagined.Battling his own grief, he teams up with a nurse who hadn't escaped the hospital when the dead began to rise. Together, they must escape the outbreak that has spread beyond the hospital walls, or else become victims of the illness they'd fought to prevent.