For a "fear of flying" group trying to overcome their phobia onboard a jumbo 747, the friendly skies are about to turn deadly. As an otherwise routine journey takes flight, a violent episode of turbulence rips through the massive plane, leaving passengers and crew disabled and a sadistic terrorist with a nerve gas bomb capable of killing millions, in control. As a terrifying killing spree unfolds, one of the group's passengers, a nerdy aircraft engineer, secretly rigs a communication line to air traffic control on land, discovering that the bomb must be jettisoned over the ocean or ground security will shoot the plane out of the sky. With time running out and the odds stacking up against them, anything can happen.