An unidentified target with erratic speed and maneuverability appears on an F-16 pilot's radar. When the flight data is given to a radio signal processing expert, he comes up with one possible explanation.
For decades, thousands of sightings of dark, delta-shaped flying objects have been reported in North America and Europe, all filed under an ominous name: "Black Triangles." Investigators are still unsure of what these mysterious craft are or where they came from. Join our investigation as we gather eyewitness accounts, expert testimony, and top-secret government files in an attempt to determine if these UFOs were optical illusions, top-secret military test planes, or the best examples of extraterrestrial visitations on record.
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