Then the steering wheel squirmed into life and started to pummel her, before mutating into a monstrous demon. The apparition sprang from the dashboard, mounted the crazed Myra and began its possession of her.
It was exactly as the women had feared. The previous evening - 17 March, St Patrick's Day - they had fled from their hometown of Arcadia in northwestern Lousiana, convinced that an evil spirit was pursuing them.
Most of what is known of their journey - including a decision, halfway, to abandon their terrified children with strangers - has been told by the women to lawyers, friends and the police.
But only one thing was recorded for certain: Myra's admission, just after dawn, to a suburban Dallas hospital. Both her eyes were missing.
Four months on, the events of that night still haunt Arcadia, otherwise famous only as the place where Bonnie and Clyde were gunned down. It is a remote, neglected little town, population 3,000, where the racial divisions of Old South still linger. The Crawford sisters - Myra, 30, who will be blind for life, Doretha, 34 and Beverly, 35 - have retreated to a shuttered brick house on Evangeline Drive, a scrubby cul-de-sac on the black side of the railway tracks.
Neighbours, slumped in the boiling summer air on their porches, hesitate to talk of the affair. Some even run away, afraid, because this is hoodoo business. 'I'm scared of them - the hoodoo, the Crawfords and all of it,' says one young woman. 'They might want pull my eyes out.'
But the secretive world of black hoodoo - a rural variant of the voodoo religion practised in Haiti and even New Orleans - may soon be laid open for all to see if, as expected, authorities in Dallas decide this week to pursue charges of criminal blinding against Doretha and Beverly.
If they go ahead, they will be overriding the pleas of Myra, who wants no charges brought, and their instincts that this case will not find much of an echo in the jurisprudence. 'Without reservation, this is the most strange case we've ever had to deal with,' says Norman Kinne of the Dallas District Attorney's office. 'This is unusual as they get - at least, here in Texas; I don't know about Louisiana.'
Lela Washington, lawyer for the accused pair, confirmed that if prosecuted her clients would plead not guilty. Crucial to the defence would be the argument that all three women were victims of an evil hoodoo hex and the blinding was the work of the demon, or indeed of Satan himself.
She cites witnesses who heard Myra speaking in a man's voice during the possession, as well as testimony from doctors at the Dallas hospital that the whoever removed her eyes - termed 'bilateral enucleation' on her admission sheet - did it with clinical precision.
The Rev Norah Banks, a Baptist minister in Arcadia who has known the Crawford family for 16 years, is convinced that the women were indeed possessed and are innocent of any crime.
'Whatever happened was beyond their control,' he said. 'They were victims of some kind of voodoo or black magic - the conjuring up of demonic spirits.'
What set the sisters on their course originally was a visit by Beverly to a local hoodoo doctor called Benny in the hope of finding a cure for recurring headaches. She was told that she was suffering because she was under assault by demons who were trying to possess her. The revelation terrified the women, and soon afterwards their father, Chester, recommended that they flee and find sanctuary with another sister in Dallas.
But their journey was hellish from the beginning. Less than an hour after leaving Arcadia down the Interstate 20, they became convinced their car was hexed, so they dumped it and rented a replacement at Shreveport airport.
After checking into a motel in Tyler on the other side of the state line in Texas, the five children started to see things. It was then that the women ordered everyone back in the car, found a house with a cross in front of it and left the children at the door.
As they were getting close to Dallas the possession of Myra occurred. Beverly and Doretha apparently beat the car into submission and managed also to calm Myra.
The three then hitched a ride closer into Dallas in a lorry, and were directed to a house that also served as an ad hoc church. It is in this place, the home of one Maddy Bradfield, that Myra apparently lost her sight forever.
It is a sequence that rings entirely true to David Otto, a professor of religion at Centenary College in Shreveport. He notes that in voodoo teaching, when a person becomes possessed by a spirit, he or she becomes the spirit's horse.
'In hoodoo lore, the spirit is riding on your shoulders, and to rid the person of that spirit, you either cut the head off, which was not appropriate in this case, or you gouge their eyes out.
'You won't be a good horse any more because you can't see, and so the spirit leaves. If you believed in hoodoo, eye-gouging would have been the appropriate response to possession.'
Mr Otto is hesitant to answer the obvious question: almost two centuries after the introduction from West Africa and Haiti of voodoo and hoodoo to the American South, how widespread are these practices today? But he does venture that in rural corners such as Arcadia, reliance among blacks on hoodoo spiritualists, as a back-up to the Christian religion and medical doctors, is likely to be common still.
For a fee, the hoodooists offer a variety of services: they can look into the future, for example. But above all, they claim powers to cast spells, either evil or benign - for clients seeking a cure from sickness, say, or success in love or work.
The survival of hoodoo, Mr Otto suggests, is due in part to the continuing sense of disenfranchisement among blacks.
'You're a rural black, you are surrounded by a culture of white people that hate you and keep you impoverished,' he says. 'In that setting, hope may be hard to find, and so would any sense of power. Hoodoo becomes a supplement to Christian faith that one needs in order to find that power and authority - and that hope.'
Mr Banks also concedes that many in his community remain wedded to hoodooism; and he regrets it.
'How many exactly, I don't know, but there are some people on almost every level who believe in it to some degree on another,' he says. 'You can't tell just by looking. I think it's probably more prevalent than any of us would know about. It's out there.'
Take one couple, Tony and Pearl, who were raised in nearby Texarkana and now enjoy a middle-class lifestyle in Houston. Tony is a banker and Pearl a teacher. Bit by bit, they confess to a long-time practice of hoodoo.
Pearl has pieces of magic wood, which she chews, while burning candles, in her attempts to ensure good fortune. 'I think it's all a bit far-fetched, but you don't know what will happen if you don't do it,' she explains.
Tony has a small red bag his mother gave him, which he believes protects him against misfortune. He does not know what is in it, but keeps it moist with olive oil. They also relate other hoodoo practices, such as how girls can attract men for marriage by feeding them spaghetti that has been dipped in their menstrual blood.
And even back on Evangeline Drive in Arcadia, one woman, Mary, confesses to an upbringing steeped in hoodoo. As a child, one day she saw the hoodoo man leaving her home, she claims, his eyes burning red and horns jutting from his head. 'Once you've seen a demon, you never forget it,' she says.