Season 1

Dr. Mark Downing, a father of two, struggles to balance his work and family life. His second born, Bailey Downing, is heading to a summer music camp, against his wishes. His first born, Landon Downing, returns home from a semester at college. When symptoms of her rare brain disorder reappear, Mark and his wife debate what to do.

After Landon faints, the Downings take her to a secret clinic run by the Sephiri Organization. Mark reveals he's been working on an experimental cure behind Elizabeth's back. As Landon's condition worsens, Mark debates administering the cure, which could have deadly side effects.

Officer Kevin Derringer visits his sister Elizabeth Downing, and learns of the turmoil within the household. A few months later, he receives a panicked call from Elizabeth and rushes to her aid. On the way, he passes a Convenience Store in the midst of an outbreak, forcing his police tactics to kick in.

Emma Gracely struggles to make a new start because of her traumatic past. Her son, Jaden Gracely, adjusts to school by attending summer classes. He meets a popular girl named Marie, who shares a similar troubled past. When the zombie outbreak hits the school, Jaden and Marie fight to reach their mothers and survive the encroaching apocalypse.