April 21st, 1977, was the date that a group of teenagers in Dover, Massachusetts, first encountered the creature that cryptozoologist Loren Coleman would eventually dub the Dover Demon. That night, William (Bill) Bartlett was driving in his Volkswagen with friends Mike Mazzocca and Andy Brodie, all of whom were 17 years old. At about 10:30 p.m., the three young men were headed northward on Farm Street when Bartlett spotted what he at first thought might be a dog or cat on top of a low stone wall. He quickly realized that his initial impression was inaccurate when the VW's headlights illuminated the entity.

The creature Bartlett saw stood three and a half to four feet tall and had a large, watermelon-shaped head, with two large, round eyes that shone like "two orange marbles"; its over-sized head was supported by a thin neck that led to an oblong torso from which sprouted long, spindly limbs. It was humanoid, with two arms and two legs, and unusually large hands and feet. The being's skin had an odd texture, "like wet sandpaper," said Bartlett, and was peach colored; although it whitened somewhat at the extremities. Neither Mazzocco nor Brodie saw the creature, both claiming to have been distracted by other things at the time; although they both vouched for the sincerity of their friend's emotion at his sighting.