In August 1984, 18-year-old Elisabeth Fritzl disappeared from her home in Amstetten, Austria.
Her father, Josef, told his wife and the police that she had run away to join a religious cult.
But the truth was far worse.
Elisabeth had never left the house. Her father had lured her into the basement, drugged her, and locked her inside a hidden, soundproof cellar that he had spent years building.
He even forced her to write letters telling her family not to search for her, then gave them to the police as proof that she was still alive.
For the next 24 years, Elisabeth remained trapped underground while the rest of her family lived directly above her.
During her captivity, Josef raped her repeatedly. She gave birth to seven of his children down there, alone, with no doctor.
One baby died shortly after birth when Josef refused to seek medical help. He later burned the body in an incinerator.
Three of the children grew up in the cellar and never saw daylight. The other three were carried upstairs as babies, where Josef and his wife raised them, claiming Elisabeth had abandoned them on the doorstep. His wife never knew the truth.
Then, in April 2008, the secret finally cracked.
One of Elisabeth’s children became critically ill inside the cellar and had to be taken to a hospital. There, doctors became suspicious when they discovered that she had no medical records and they could not contact her mother.
Josef eventually brought Elisabeth to the hospital, where police separated them.
After officers promised that she would never have to see her father again, Elisabeth told them everything.
In 2009, Josef Fritzl pleaded guilty to rape, enslavement, incest, false imprisonment, coercion, and murder by negligence. He was sentenced to life in prison, where he remains.
Elisabeth was 18 when her father locked her underground. She was 42 when she finally walked free.