A groundbreaking 2017 story in the New York Times reveals that the Pentagon secretly spent years studying UFOs, casting new light on decades of unexplained UFO sightings in America - like the 1997 Phoenix Lights encounters and the 2006 Chicago airport sighting. Has first contact already been made, and if so, why is the US government trying to cover it up? Series premiere.

UFO sightings don't just come from crackpots: in 2004, a team of elite Navy pilots and radar operators had one of many military encounters with unidentified aerial phenomena. As evidence mounts, the government, along with alien-obsessed billionaire Robert Bigelow, grow more interested in UFOs and the paranormal.

As the world reeled from the New York Times bombshell that revealed the government's interest in UFOs, a few dissenting voices suggest that what looks like sincere interest might actually be a disinformation campaign. Is the U.S. government covering up the existence of aliens?

Even as the New York Times brought credibility and a broad audience to the question of UFOs and extraterrestrial life, other figures challenged whether it might all be a great big lie.