Mary Vincent came face-to-face with a killer. This is her story of survival.

CONTENT WARNING: This post contains details of violence and sexual assault.

Mary woke from her nap. As her eyes began to focus, they fixed upon a road sign that rushed past the window of the van. It looked different somehow. Wrong. The fog of sleep lifted and the 15-year-old realised. East. They were heading east.

She mustered courage and turned to the driver, a paunchy, grandfatherly man who had picked her up in Berkeley earlier that afternoon. “Look you’re going the wrong way,” she said, “and you know you’re going the wrong way.”

Just an honest mistake, he insisted, nothing to worry about. He’d just have to stop briefly to relieve himself, then they could continue on their journey to Los Angeles.

They drove for a short time, then the van peeled off the freeway down a side road that seemed to lead toward the canyon. Mary’s instinct overpowered her naïvety. The area was isolated and the road deserted. She was a prisoner.

‘I’m young; he’s old,’ she thought, her mind racing. ‘I’m healthy; he’s not.’ She could outrun him, she could get away, get help. But she’d need to tie her loose shoelace if she had any hope.

Once he’d closed the door behind him she opened hers, and bent down toward her foot.

Then came the blow of the sledgehammer.

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It was 1978. Mary Vincent had done what many teens had before and many have in the decades since. She’d run away from home.

Raised in fast-and-loose Las Vegas, she was the middle of seven children in a military family. According to a People article published 10 years later, she’d cut classes, wore makeup, generally rebelled against her strict parents. Then came the day when Mary’s sister warned that their father was on his way home with a migraine and was angry at her.

She fled in a hurry, she later told the Seattle Post-Intelligencer, to save her life.

Mary stayed with her boyfriend for a time in Sausalito, California, then, between nights sleeping rough, with an uncle in the small town of Soquel. It was from there she left on the morning of September 28 to hitch the 620km to her grandfather’s place in Los Angeles.

Standing with two other hitchhikers, clutching her sign, a man pulled up in a blue van, empty but for a single bag – yet he only had room for one of them, for her. Ignoring the warnings of the others, she climbed in.

“I wasn’t a daredevil or anything,” she said in an interview on television program I Survived. “I was just desperate to get home. I could not live another day out, alone. I didn’t think about what type of person he was or the situation. I was… I was tired.”

That person was Lawrence "Larry" Singleton, a then 51-year-old merchant mariner, with blue overalls, a bulging stomach and a flat, bulbous nose.

One who later hit Mary Vincent twice with a sledgehammer, tied her hands and raped her in the back of his van. Who then climbed, naked, back into the driver's seat and drove farther down the road toward the canyon where he raped her repeatedly throughout the night and forced her to swallow liquor.

The hours passed slowly. Terrified, exhausted, in searing pain, she pleaded with Singleton over and over throughout the ordeal. "Just set me free," she begged. "Please, just set me free. I won't tell."

As the darkness began to shrink across the sky, he walked to the rear of the van, and returned with a tool box. As he loomed over her, he pulled out a hatchet. "You want to be free?" he yelled. "I'll set you free."

Then he swung.

He struck her left arm first, severing it just below the elbow. As he hacked at her right, she kicked him, furiously, desperately, screaming both for help and in agony.

"I felt all the pain; the sharpness, the burning. And as the blood was leaking out of my body I felt the hot ooze just flowing out of me," she told I Survived. "I felt everything. I was aware of everything."

By the time he finished his attack, Mary was limp but conscious. But Lawrence Singleton didn't know that. Presuming she was dead, he dragged her body across the dirt then threw her off a 9-metre cliff into a concrete culvert.

She should have died there. Half of her blood had leeched from her body and the rest was fast becoming toxic.

But Mary heard a voice - a voice, she says, that was in her mind, her heart and her soul. "I can't go to sleep," it said. "He's going to do this to somebody else. I can't let that happen."

She summoned energy and rolled her elbows in the dirt to coat the wounds and stem the bleeding, and scrambled back up the cliff. The sound of traffic guided her through the darkness toward the freeway, where she walked, naked, with her arms raised - a court report said - "so that the muscles and blood would not fall out."

A red convertible with two men inside slowed, then sped off again when she called for help. Then came her saviours. Two holidaymakers who had gotten lost. They helped her into their truck and raced to a phone to call paramedics.

In March 1979, a San Diego jury convicted Lawrence Singleton of kidnapping, mayhem, attempted murder, forcible rape, sodomy and forced oral copulation.

His teenage victim, now fitted with prosthetic arms, was there.

“When he was done testifying and I was leaving the courthouse I had to pass him, just inches away, and I hear him say, ‘If it’s the last thing I do, I will finish the job.’”

Singleton was slapped with a 14-year jail term - the maximum available in California at the time. And yet he served just eight, paroled for "good behaviour".

The resulting outrage ultimately changed sentencing laws in California that would have seen Singleton imprisoned for 31 years. But it was too late for his second victim.

Back home in his native Florida, were he had been in and out of jail (petty theft) and psych wards (attempted suicide), Singleton stabbed 31-year-old sex worker and mother of three Roxanne Hayes to death in his living room in 1997. When police arrived they found him standing over her body, his shirt splattered with blood.

"I'm not going to say he's Hannibal Lecter," prosecutor, Donald N. Stahl, told The New York Times at the time, "but once a guy like that has a certain bent he follows it the rest of his life."

Singleton was convicted and committed to death by a Florida Court.

Mary, now in her 50s and the mother to two adult sons, doesn't use his name. "My attacker", she calls him. The man who took her arms, her innocence and left her with little but that haunting threat and traumatic memories.

"I've broken bones thanks to my nightmares," she told the Seattle Post-Intelligencer. "I've jumped up and dislocated my shoulder, just trying to get out of bed. I've cracked ribs and smashed my nose."

Yet when Lawrence Singleton died of cancer on death row in December 2001, it wasn't relief that Mary felt.

"I needed to know what was in that dark soul of his. I felt I was robbed of that opportunity," she said on I Survived. "But because of my sons - I saw the relief on their faces - that made me realise, OK, that’s good enough closure for me. I don’t have to worry about my son’s lives anymore."

Mary finds joy and hope in her art (she paints), her children and her faith, and in the second chance she was given in the face of such evil.

“I never knew there could be people like that in the world," she told I Survived, "and I pray to God I never know another.”