A flu virus emerges in Mumbai, India. For weeks, no one is concerned. After all, the flu appears every year. But this virus is different. It has one unusual symptom. Some of those infected with the virus become enraged. They become violent and destructive. As the virus progresses, the Rage, as it is being called, begins to concern world governments. Something has to be done to stop it. ? Mick Delaney, CEO of the pharmaceutical company Immutrends is called on by the president of the United States to develop a vaccine for the Rage. From that research, Mick discovers something inexplicably frightening: the Mumbai Flu, the Rage, will eventually evolve into an Ebola variant, something Mick names Ebola Air. That airborne virus could have a mortality rate of over 90 percent. It could lead to an extinction-level event, one that would all but destroy mankind. ? Because of the potential for such a threat, Mick and his partners, Grant Tracer and Emily Adkins, design a vast underground shelter to be built in the Montana wilderness. The project, called the Core, will allow up to two hundred members to be protected from the pandemic for up to twenty years. Members will be sent a signal when it is time to travel to Montana. Inside the Core, his team will attempt to find a vaccine for Ebola Air. But there's a larger question-how did a flu virus mutate into an Ebola strain?