Is it chasing us? That thought coursed through Betty and Barney Hill’s minds as they drove down the empty winding country road in New Hampshire’s White Mountains. It was a September night in 1961, they hadn’t seen a car for miles, and a strange light in the sky seemed to follow them.

When they finally got home to Portsmouth at dawn, they were far from relieved. They felt dirty. Their watches stopped working. Barney’s shoes were strangely scuffed and Betty’s dress was ripped. There were two hours of the drive that neither one of them could remember. What had happened?

With the help of a psychiatrist, the quiet couple eventually revealed a startling story: Gray beings with large eyes had walked them into a metallic disc as wide, Betty said, as her house was long. Once inside, the beings examined the couple and erased their memories.

Their experience would kick off an Air Force inquiry, part of the secretive initiative Project Blue Book that investigated UFO sightings across the country. The incident would also become the first-ever widely publicized alien-abduction account and shape how stories like it were told—and understood—from then on. Debate continues as to whether the husband and wife were liars, fantasists, crackpots or simply sleep-deprived people who later recovered seriously scrambled memories.

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Strange lights in pursuit

An illustration of Betty and Barney Hill's 1961 alien abduction. API/Gamma-Rapho/Getty Images

The Hills’ road trip was spontaneous, a well-earned break Barney decided the couple needed, as explained in The Interrupted Journey, a 1966 book they collaborated on with author John G. Fuller. Barney worked a grueling night shift at the post office, driving 60 miles each way. Betty’s job handling state child-welfare cases was no easier. The little free time this biracial couple had was devoted to their church and activities related to the civil-rights movement. After 16 months of marriage, Betty and Barney saw this trip through Montreal and Niagara Falls as their delayed honeymoon. They left so impulsively they had no time to go to the bank before it closed for the weekend. They got in their car with less than $70 in their pockets.

On the last night of their three-day trip, the tired couple sipped coffee in a Vermont diner to recharge before driving back. Barney figured if they pushed through, they could beat the wind and rains from an approaching hurricane. They left the diner around 10 p.m., estimating they could reach their red-framed house in Portsmouth, New Hampshire between 2 a.m. and 3 a.m. at the latest.

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As they drove, strange light in the sky gave another reason to hurry. At first it looked like a falling star, but grew larger and brighter with each mile. Barney, an avid plane watcher and World War II vet, was sure they had nothing to worry about. It’s just a satellite, he assured Betty. It probably went off course.

The light seemed to move with the car as Barney steered down the curving mountain road. The light zigged and zagged, ducking past the moon and behind trees and mountain ridges, only to reappear moments later. Sometimes it seemed to move toward them in a game of cat-and-mouse. It had to be an illusion, they thought. Maybe the car’s movement made it seem like the light, too, was moving.

Curiosity overcame them. The couple pulled over at road stops and picnic turnouts to get a closer look. Through binoculars, Betty saw that the white light was really an object spinning in the air.

“Barney,” she told her husband, “if you think that’s a satellite or a star, you’re being completely ridiculous.”

The close encounter

He knew she was right. Barney had an IQ of 140, noted Fuller in his book. Barney was also a pragmatic man who wouldn’t give flying saucers a second thought, remembered his niece Kathleen Marden in her work, Captured: The Betty and Barney Hill Experience. The night was too quiet for a helicopter, a commercial plane or even military jet with a hotshot pilot. He didn’t want to spook Betty, but he was becoming concerned. What was this light and why was it toying with them?

About 70 miles past the diner, the object hovered just above the treetops, approximately 100 feet above them. Barney abruptly stopped the car, keeping the engine running. He shoved a handgun he’d hidden beneath the seat into his pocket and rushed into a dark field, leaving Betty in the car. What he saw was as big as a jet but as round and flat as a pancake. “My God, what is this thing?” he recalled thinking. “This can’t be real.”

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Behind rows of windows, gray uniformed beings seemed to look right at him, Barney recalled. He tried to lift his hand to his pistol but somehow couldn’t. A voice told him not to put down his binoculars.

He had a startling thought: We’re about to be captured. Yelling hysterically, he ran back to the car and barreled down the road as Betty tracked the craft, craning her head outside the car window. Without explanation, loud, rhythmic beeps sounded from the car’s trunk. The couple felt instantly drowsy and lost consciousness.

They came to around two hours later and 35 miles down the road.

Recovering the memory

Image depicting an alien space ship, at 200 feet and 100 feet above the Earth's surface, drawn by alleged alien abductee Betty Hill and regarded as one of the first examples of the Flying Saucer alien spaceship archetype, September 20, 1961. University of New Hampshire/Gado/Getty Images

Back home in Portsmouth, they tried to make sense of the night. Barney felt compelled to examine his body’s lower half. Both seemed aware of a puzzling presence.

In the weeks and months after, Betty, an avid reader, checked out books from the library discovering the civilian UFO group National Investigations Committee on Aerial Phenomena (NICAP). She also reported the sighting to the Air Force, worried about radiation.

In coming years, with Betty suffering from disturbing dreams and Barney developing an ulcer and anxiety, the couple sought mental help. The two met with Benjamin Simon, a psychiatrist and neurologist who specialized in hypnosis, a mainstream technique at the time.

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Through months of weekly sessions, Simon helped the couple piece together what they think had happened: A vessel had landed on the Hill’s car, putting them to sleep. Afterward, gray beings walked them up a long ramp and into the spacecraft.

Once inside, the Hills were separated, taking turns in an examination room that had curved walls and a large light hanging from the ceiling. Each was asked to climb up on a metal table. The table was so short, Barney’s legs hung over the side.

During the examinations, the beings removed Betty and Barney’s clothes, plucked strands of their hair, took clippings of their nails and scraped their skin. Each sample was placed on a clear material, not unlike a glass slide. Needles, connected to long wires, probed their heads, arms, legs and spines. One large needle, around 4 to 6 inches long, was inserted into Betty’s belly. This pregnancy test left her twisting in pain. Throughout, a being Barney and Betty called “the leader” watched from the side.

After Betty’s examination ended, the beings rushed back into her room, excited. They discovered that Barney’s teeth could be removed. Betty laughed, explaining that Barney had dentures, a fact of human aging the beings struggled to understand.

Later, alone with the leader, Betty asked where the craft had flown, admitting she knew little of the universe. The being joked with her, saying “if you don’t know where you are, there wouldn’t be any point in telling you where I am.” Later, under hypnosis, she drew a star map shown to her on the ship.

In 1965, the Hills' story was picked up by a Boston newspaper. After that, everything changed. The quiet couple’s story became the subject of a best-selling book and a movie starring James Earl Jones. The upstanding civil servants had become celebrity abductees.

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The model for alien abductions

Barney holding up a diagram explaining the alien abduction. Bettmann Archive/Getty Images

The Hills weren’t the first to spot a UFO or even to report an abduction. But their story did capture the nation’s imagination and was so widely publicized, it has helped shape how we talk about alien encounters and abductions to this day.

Before the Hill’s story, alien encounters were friendly, according to Christoper Bader, a professor of sociology at California’s Chapman University. Some aliens even lived on earth and commuted back on weekends. But once the Hills’ story became better known, abduction accounts shared certain characteristics, such as medical examinations and missing time. Aliens with large heads and big eyes—dubbed “grays” in UFO circles—became classic sci-fi staples in personal accounts and pop culture, Close Encounters of the Third Kind and shows like the X-Files.

The Hills’ story—and those that came after—helped pave the way for a new understanding of human experience. Richard J. McNally, a Harvard psychologist, puts it this way: “The ‘alien-abduction’ phenomenon, in my opinion, shows how sincere, non-psychotic individuals can develop beliefs about, and false memories of, incredible experiences that never happened.”

Experts of all stripes have tried to explain why intelligent, otherwise mentally stable people came forward with these experiences. Many psychologists say sleep paralysis and hallucinations played a role. Leading questions during hypnosis—the main way most abductees unlock their stories—could also have been a factor.

A view into the human brain

Barney and Betty Hill holding a newspaper reporting about their alleged alien abduction in a rural portion of New Hampshire in late September 1961. Universal History Archive/Getty Images

Those who report abduction might also see the world a little differently. According to research, one of the strongest predictors of false recall is a vivid imagination. This group scores high in “magical ideation” and is more likely to believe in ghosts and tarot readings, according to McNally.

Some believe the Hill’s story was simply a myth in the making, with the supernatural meetings, vulnerable protagonists and otherworldly journeys that are often the hallmarks of legend. Many point to the stress of being an interracial couple living in a predominantly white state in a turbulent era. (The year of their hypnosis, 1964, was marked by Cold War tensions and civil-rights unrest, with numerous urban riots erupting that summer.) “You have a biracial couple at a time where obviously it was not easy to be a biracial couple,” says Bader. “Look what those aliens were: a mixture of black and white. I find that very meaningful.”

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Abductee stories depend on first-hand accounts—the most vulnerable form of evidence. Memories can be distorted by stress or distraction, or even manufactured. When a false memory is in place, psychologists say, the brain works to fill in the details. Psychologist Michael Shermer points to ‘patternicity,’ the tendency to see patterns even when none exist, helping us to see faces in clouds or assume that one event caused another.

Past experience also shapes human perception. Barney, a World War II vet, thought the head “gray” looked like Hitler and seemed menacing. Betty, meanwhile, who had been excited to see the aliens, bantered with the affable gray who performed her medical examination. That alien even agreed to give her a book to bring to earth with her, she said, though other crew members would later overrule that decision.

In this way alien abduction and encounter stories have helped psychologists understand the human brain, its defects—and the weaknesses inherent in memory and first-hand accounts, according to Christopher French, a psychologist specializing in human experience related to the paranormal. “What we see and hear, especially under less than ideal observational conditions, can be heavily influenced by our prior beliefs and expectations,” wrote French in the The Guardian.

NICAP’s scientific advisor cross-examined the couple and found their account credible. The Air Force’s Project Blue Book would ultimately dismiss the story, determining the unexplained craft could be explained by “natural causes”—hinting that the couple hadn’t seen a spacecraft but only the planet Jupiter.

For his part, psychiatrist Simon never felt the Hills had made up their story. He concluded Betty had dreamed the abduction and Barney had absorbed her story, especially since many of the most vivid details matched descriptions of dreams Betty had jotted down after the event. “I believe implicitly in the honesty of these people,” he said on a ‘70s radio program.

Of course, another explanation is always possible: The abduction actually occurred. The Hills stuck by their story, despite years of skeptics and detractors. Like many abductees, the couple never felt false memory or sleep paralysis explained what they experienced. Betty became a known voice in UFO research and claimed she was visited multiple times in the decades to follow.

WATCH: Full episodes of Project Blue Book online now.