Made-for-TV sci-fi drama starring Glenn Ford and David Soul. At 10.30 hours at Whitney Airforce Base, Shadow Delta One prepares for take-off on a routine flight. The routine is shattered when Blanco Vista Marine Airbase picks up three blips following Shadow Delta One an hour and a half later. A squadron of Marine Jets is scrambled to investigate the unidentified blips, but they and the UFOs disappear when contact is about to be made. In the following hours the ground crew tries in earnest to discover the fate of Flight 412, as well as the planes sent to find it.