Miles O’Connor knows a deadly secret and works at a black site in New Mexico. A lethal weapon, the Pythagoras Project, is in development. O’Connor is part of the team, but when he discovers the full range and plans for the weapon, O’Connor destroys his work and disappears. Phoenix, Lydia, Julian and Yuma are strangers, flying to see loved ones for Thanksgiving. In a terrifying moment, their plane falls from the sky and plunges to the ground, in the middle of a Montana forest. Grateful to have survived, they must find their way out of the forest when no one comes to rescue them. To their utter disbelief, the world has changed in a split second and they must fight to survive. What does O’Connor know that the rest of the world doesn’t? What happens when Pythagoras Falls?