Teen held captive in storage container for nine months speaks out

Warning: Content may disturb

The teenage girl held captive in a storage container in New Hampshire by a violent predator who abducted her on her way home for school has spoken out about the horror she endured, four years after escaping his lair.

Abigail Hernandez, now 19, was abducted by Nathaniel Kibby, 39, as she walked home from school in Conway, New Hampshire, in October 2013.

The zombie apocalypse-obsessed abductor had offered her a ride home and she accepted because her feet were blistered from the boots she was wearing, the Daily Mail reports.

For nine months, he held her captive in a shipping container stashed on his rural property. Kibby forced her to wear a shock collar which struck her if she screamed and he sexually assaulted her repeatedly.

In an interview with ABC'S 20/20 which will air on Friday, Hernandez, whose identity had been protected in the past because she is the victim of sexual crimes, spoke about the time she spent in captivity.

She revealed that Kibby, who is now likely to spend the rest of his life in prison, would not tell her his name and instead instructed her to call him 'master'.

The young woman also explained how he started using the dog collar on her.

"He said, 'You know, I'm thinking of finding something a little more humane for you to keep you quiet.'

"He said, 'I'm thinking of a shock collar. You know, that like dogs wear.'

"I remember he put it on me. And he told me, 'Okay, try and scream.'

"I just slowly started to raise my voice. And then, it shocked me. So, he's like, 'Okay, now you know what it feels like'," she said.

In July 2014, Kibby suddenly decided to let the teenager go.

It took her a week before she revealed to her family and law enforcement agencies who he was because she was so afraid of him.

She knew his name because she had seen it written on a cookbook inside the home.

Kibby was arrested at his home which was nearly 50km north of where he took Abigail.

In the nine months she spent in his captivity, she was only ever allowed to write one letter to her family under his instruction.

After his arrest, she bravely confronted him in court and thanked him for letting her go.

"I want you to know that I appreciate my freedom because of you and I enjoy my life because of you. I just want to thank you for giving me my freedom back," she said.

Kibby was sentenced to a minimum of 45 years behind bars and was charged with a litany of crimes including kidnapping and sexual assault.

He said he decided to let Abigail go because he'd "terrorised her enough".

Neighbours testified at his sentencing hearings that he was a gun-obsessed loner who was convinced there would be a zombie apocalypse.

They said they half expected him to unravel and do something violent but that kidnapping a child was one of the last things they predicted he would do.