The 1991 crash of Atlantic Southeast Airlines Flight 2311 to Brunswick, Georgia claims the lives of a NASA astronaut and a former U.S. senator and becomes an international media sensation. Commuter planes like this twin-turboprop aircraft aren't required to carry flight recorders, so investigators must rely on physical evidence to find the cause of the disaster. The strange angle of one of the propeller blades seems to offer an explanation, but in order to prove the detectives' theory, they'll need to take a huge and potentially lethal gamble.