The Grinning Man was apparently first
in 1966, according to John Keel, the paranormal investigator mostly know for his book
The Mothman Prophecies.
The story about the Ginning man involved 2 boys walking along a street in New Jersey in October 1966. The boys were walking in the same area that earlier that day a woman had reported being chased by a “tall, green man”, and the two were nervous about the story. They were to report later that they saw perhaps the same man, standing behind a fence in some brush, looking at a house across the road from the boys.
The being was behind them, and was wearing a green one-peice suit that reflected the streetlights nearby. It noticed the boys looking at him, turned and began to smile – a grin that stretched from ear to ear. Having elongated eyes, the boys could not make out whether the creature had ears, a nose or hair.
That same night, miles away, reports of a “bright-white” UFO began filtering in to the police, and several officers reportedly saw the object themsleves hovering near a local reservior.