Columbia Airlines Flight 409 takes off from Washington DC on its way to Los Angeles. When flying over the mountains a small plane's pilot suffers a heart attack and smashes into the cockpit of the Columbian 747. Killing the flight engineer and co-pilot. And leaving a blinded captain. In desperation head stewardess Nancy Pryor (Karen Black) takes the controls. But the radio is going dead and only a suspense filled rescue mission can save them all.