For many years there have been reports of a strange creature roaming the interior of Buenos Aires province. Most reports came in from Luis Guillon, district of Esteban Echeveria. A rural area known as Luis Guillon, is made up of several barrios. Among them there is Barrio Lindo, Barrio Las Moreras, Barrio Lavallol, and Barrio Bahia Blanca.

At the border of Barrio Lindo and Barrio Las Moreras there is a big Estancia, and at the farthest point of Barrio Lindo there is an old cemetery. It is around these barrios that the legend of this creature begun. Some said that it was a werewolf, others that it was a ghoul that robbed the cemetery and ate the corpses, and even others said that it was a demon looking for victims to possess.

It was at the beginning of 1960 that sighting of this creature begun to increase. Tales of seeing a terrifying form, some say it crawled on all four, some say it ran hunched over like an ape, some even said that it moved in a rolling motion on the ground, were common. Each sighting mentioned a pack of wild dogs. Some said that the creature was chasing it, following it, or running with it.

These local people were prone to superstitions, and wild imagination, so for sometime they we not taken seriously. But reports continued to come in. People in those barrios were afraid to come out at night. When they heard their own dogs begin to bark at night, these people would go into a panic, many praying out loud, crying, and such.

The situation started to take a critical turn when a young boy was almost stoned to death by these peasants as he was accused of being the werewolf because he was the thirteenth boy in a family of thirteen children, all boys. Then, an adolescent girl was brutally attack one evening. Even though her assailant was soon caught, people there claimed that he was just a scapegoat so the authority would say that they have solved the mystery.

For the national media all this was a big joke. They would bring people dressed up in gorilla suits or werewolf masks, during the day, running down the main boulevard, while the reporters yelled, “there's the demon of Luis Guillon!” The locals did not laugh.

Finally, the local commandant for Luis Guillon put together a team of officers who were deputized to find this “creature of the night.” They were sent out in teams of two, and there were three teams. Team number one came to Barrio Las Moreras; team number two went to Barrio Lindo by the cemetery; team number three were set up inside the forest area of the estancia where the creature was last sighted.