The Antonio Villas (some sources spell it Vilas) Boasalien abduction, while not the first such supposed occurrence, was among the earliest to attract wide public attention.
The story begins in November 1957 with the arrival of two letters in the mailbox of noted Brazilian journalist Joao Martins, who having allready written several articles about UFOs and having placed an add in the newspaper was looking for material to write another. In the letters a supposedly poor farmer from the Brazilian interior, 23 year old Antonio Villas Boas related a story of kidnapping by extraterrestrials, a tale so incredible that it piqued the writer’s curiosity to the point where he contacted a Rio de Janeiro doctor by the name of Olavo Fontes and showed him the correspondence. The two decided the story warranted further investigation and sent Boas the fare in order that he might travel the several hundred miles from his home in Sao Francisco de Sales to the doctor’s office.
Upon arrival, Boas was examined by Fontes who concluded the farmer was suffering from a mild case of radiation sickness, a diagnosis in keeping with Boas’s claims of nausea, headaches, skin lesions and general lethargy.
Later in more detail and without benefit of hypnosis Boas retold the tale he had originally laid out in his correspondence and except for periods of embarrassment engendered when discussing certain sexual details the story flowed in a rational, straightforward and unimaginative manner.
Preferring to work in the cool of the night and leave the hot scorching days to his brothers, Boas was alone in his family’s fields on October 16, 1957, when around 1 a.m. a red light appeared in the night sky, as it approached it grew in size eventually becoming recognizable as an oval shaped flying craft. Swooping low overhead the object suddenly stopped extended three legs and landed close by. Frightened the farmer tried to escape but the tractor with which he had been ploughing had other ideas its engine and lights dying after only a few feet. Jumping down from the now useless machine he attempted to continue on foot, only to be seized by first one then three more helmeted and uniformed humanoids. All four then proceeded to drag him screaming and kicking into the UFO. 
Inside he found himself in a small brightly lit featureless room, from there he was taken into another room his clothing removed and his body covered in a thick gel. He was then taken to yet another room where two aliens extracted blood before leaving; shortly afterward a foul smelling gas permeated the area and made him violently sick.
More minutes passed, before startled by a noise Boas turned and beheld a short naked humanlike woman with catlike eyes and long white hair. She seduced him making barking noises as she did so. After the sex act the woman rubbed her stomach, pointed upward and departed. The confused farmer took this to mean that she was going to have his baby somewhere up in space.
His clothing was returned to him and Boas dressed before being taken on a tour of the ship. An attempt to remove a clock like object as proof of his encounter was summarily blocked by his guide, who then escorted him off the ship, which following his departure rose into the air and moved away at great speed finally disappearing in the distance. After returning home Boas checked the time and discovered that four hours had passed.
The simple farmer didn’t remain that way for long, finishing his schooling by way of correspondence courses he eventually became a lawyer, married and became the proud father of four children. He died in 1992 maintaining to the very end that his encounter was genuine and his depiction of events both accurate and truthful.
Was it a hoax, something else or was Villas Boas really abducted?
Some have argued that Boas was a poor illiterate peasant and that if his story had been fabricated it would have been done with the intent of selling it for money, they maintain that though in need of money the fact that he never chose that course should speak volumes for his integrity. But was he poor? The fact that his family owned a tractor says no, peasants in 1957 Brazil definitely couldn’t have afforded the significant investment that owning a tractor would have entailed. Was he illiterate? Well again the answer has to be no, he eventually became a lawyer and no matter what we may individually think of these so called purveyors of justice they are rarely if ever illiterate.
It may be that Boas truly believed he had been kidnapped by aliens, the victim of an hallucination occurring while he was in some sort of trance:
During the 1970s a teenager from Deeside, North Wales, was allegedly abducted a number of times by aliens being transported from her bedroom by spaceship to the extraterrestrial’s home world. That the occurrences were hallucinations was revealed when her mother entered her daughter’s bedroom, one night, to find the youngster in a catatonic state a sleep so deep it frightened her. Checking back later she found her daughter sleeping normally. The following morning the youngster reported excitedly that she had been abducted yet again.
Then again maybe he was the victim of an extraterrestrial abduction:
At 3 a.m. on a late November night in 1989 a New York native and past abductee by the name of Linda was to experience what has been billed in UFO circles as the so called “case of the century.” After being placed in a state of hypnotic regression by abduction therapist Budd Hopkins, Linda told of being floated out the window of her twelfth story Manhattan apartment along with several alien attendants, then transferred into a waiting spacecraft where she underwent various medical procedures before being returned to her bed. It would have been just another wild abduction story, except for one thing this time there were allegedly witnesses.
In a letter mailed to Hopkins, two intelligence officers claimed that they and a third person, purportedly a high level member of the United Nations, were returning from a secret meeting when their automobile’s electrical system failed, stalling them in just the right spot to observe the bizarre event. They also stated that going public with the information was out of the question as it would compromise the official they had been transporting.
Other witnesses were to follow all with basically the same story, cars stalling at a time and place which allowed them to view Linda’s aerial abduction.
 Boas drew two sketches of the alien craft, one for Dr. Fontes and later another for Drs. Buhler and Aquino of the Brazilian Society for the Study of Flying Saucers.