After WWII, thousands of UFO sightings were reported to the U.S. Air Force, who investigated these cases very seriously. We take a look at one mysterious report from 1949, filed as "Incident 398."
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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