Two massive events fell from the sky, flattening forests and igniting decades of speculation. One sparked theories of comets and asteroids; the other launched the modern UFO phenomenon. We examine what these twin mysteries reveal about how evidence, timing, and culture shape the stories we tell about the unexplained.

From the haunting Zodiac Killer's 340-character cipher to the mysterious Voynich Manuscript, some codes have resisted centuries of attempts to crack them. Join us as we count down five encrypted messages that continue to perplex cryptographers, historians, and amateur sleuths around the world. Could you be the one to finally solve them?

On December 5, 1945, five TBM Avenger torpedo bombers took off from Fort Lauderdale on a routine training mission—and were never seen again. Neither was the rescue plane sent to find them. We investigate the confusing radio transmissions, the frantic search efforts, and the competing theories about what really happened to the 27 men who vanished that day.