Natascha Kampusch, the Austrian kidnap victim, has revealed in a new film that her captor shaved her head, forbade her to cry and brutally abused her during the eight years she was held in the cellar from which she escaped in August 2006.
Kampusch, who is now 21, was abducted at the age of 10 on her way to school in Vienna, in one of the most sensational kidnap cases in Austrian criminal history.
Her captor, an electrical engineer called Wolfgang Priklopil, committed suicide only hours after she escaped, emaciated and ashen-faced from lack of daylight.
Yesterday, more disturbing details about her ordeal emerged following a preview of a new autobiographical documentary which will be shown on Germany's ARD channel in January.
In the film Kampusch revisits the cellar where she was held.
"I am a victim of violence and I will remain marked for the rest of my life because of what happened to me," she says on camera.
The film, entitled 3,096 days held prisoner, is a grim, mainly first-person account of Kampusch's captivity.
She recalls how she was suddenly dragged into the back of a white van in a Vienna suburb one day in March 1998 and couldn't cry for help because her vocal cords were paralysed by fear.
She was then driven to 44-year-old Priklopil's house and bundled into an underground cell in a converted 2.7m by 1.8m car inspection pit.
To enter she had to crawl through a 48cm by 48cm hatch that was sealed by a large steel door.
Ms Kampusch recounts that early on in her ordeal it took Priklopil up to a hour to get into her cellar prison because he had to get through two other locked doors and heaps of junk furniture that he had piled up in front of them.
"I was like an Egyptian pharaoh conserved alive," she says.
When she arrived she was forced to take off her shoes and told: "You won't be needing them again."
She soon lost track of whether it was day or night.
"It was cold, damp and disgusting," she says in the film.
Much of her time was spent in darkness interrupted by a timed light which came on and off, "as in a real prison".
At first she could only speak to Priklopil through an intercom system linking the cell with her captor's home upstairs.
As the years went by, Priklopil began to allow his captive, who had by now been reduced to a slave, to visit him upstairs.
She recalls how Priklopil was a "hygiene fanatic" who first forced her to enclose her hair in a plastic bag, and when that wasn't enough, shaved her head bald. She was forbidden to cry. If she left fingerprints on any surface she was severely punished.
"Then I would be abused," she said.
"I preferred being in my cell than upstairs," she adds.
Kampusch does not reveal whether she had sex with her abductor but insists that she was not used for child pornography.
She managed to escape, aged 18, by running into a neighbour's garden after her captor ordered her to vacuum his car and then let her out of his sight when he went to answer the phone.
Peter Reichard, the scriptwriter of the film, said Natascha Kampusch and her mother had been treated with a mixture of aggression and disapproval in Austria.
As a result they had turned to German television to make the film.
"I wanted things to be shown from a different perspective," Kampusch said.
"In Austria I hardly go out."