The night before twenty-one-year-old Carly Shanahan takes her little brother and three friends on a three-day caving expedition, Sanford, the elderly eccentric owner of the cave, begins to quote quatrains written by Nostradamus. The next day, shortly after entering the cave, an earthquake traps the group inside with the old man and his notebook. Twenty miles away, a cluster of prisoners on a work release program inside a coalmine plans an escape. Just as the prisoners, led by a vicious psychopath, brutally murder two guards, the same earthquake also traps them underground. Days later, when both groups finally escape from their subterranean confinement, the world is a very different place. Is it possible Sanford is actually a conduit, prophesizing from the past? Did he somehow know that world-changing events were about to unfold? Carly must use Sanford and Nostradamus's quatrains as a guide to find a way to save her companions while also somehow preventing the extinction of mankind. She might not be prepared to play the role thrust upon her, but the fate of her friends and the world now depends on her ability to make the right decisions.