Which NCIS episode featured the investigation of a crop circle?!
Question: And what was the conclusion to the mystery.
Answers: And what was the conclusion to the mystery.
That would be Vanished.
And the answer to the mystery is the pilot brought the helicopter there to rescue his brother, who had already been killed by some of the locals. He was out for revenge, while they faked a crop circle to divert NCIS from what was really going on.