It is human nature to look away some times when confronted with a terrible problem. To night you meet a married couple. Christian missionaries who not only refused to look away they up-ended their... See More
It is human nature to look away some times when confronted with a terrible problem. To night you meet a married couple. Christian missionaries who not only refused to look away they up-ended their lives even risked their lives to help vulnerable young women. Here is ABC's Byron Pitts. If hell had a who house thwhorehouse, this region, home to 10,000 prostitutes many teenaged girls. Most sold into the sex trade by their families, like cattle to a slaughterhouse. They are seen by society as untouchable. Reporter: Untouchable until Kerry and Annie Hilton stumbled upon them literally. The preacher and wife left new Zealand to come to India to do missionary work but had no idea their new apartment overlooked the largest sex bazaar in India that is until the sun went down. I personally hadn't left new Zealand with an 11-year-old daughter to think I would be living in a red light area. Reporter: Why didn't you then pack the next day, and forgive me, run like hell? We felt that these women straight away were our neighbors. Reporter: That was 15 years ago. Undeterred they stayed. Raised their children. And unbelievably decide to take on India's billion dollar sexen Dus trsexen -- sex industry. Rescuing these girls one at a time. We wanted them to have a choice. They never had before to. Provide an economic solution a first step. Reporter: They created a company, burlap bags and cotton t-shirts built on a bold model. We don't hire based on experience and skill. We hire on the basis of, a need to be free. Reporter: What started with 20 women today employs more than 200. Some of the girls they become stars. Reporter: Stars like this girl. Her mother was a prostitute. Groomed for the same fate she witnessed things no child ever should. It was safer for her how to come and work with us. But actually for me she was the example of the future generation. Where the cycle can be broken. She lives a life her mother can never imagimagine? We are so proud of her. Reporter: In India's dangerous sex trade, saving a woman's life also means you are cutting into some one else's profits. Some body rang up threat tuned kill us. Reporter: Threat tuned kill you and your wife? Actually if we didn't pay, a lot of money. And quite a conversation. Reporter: Did you pay? Absolutely not. Reporter: Now the hiltons are expanding their business opening shops in small villages that have fed India's brothels for generation. A new crop of poor and desperate girls year after year. Reporter: Yours is not a drive-by solution. Our solution is what we will do for the rest of our lives. Reporter: Blind faith may have brought them to India. But crystal clear sight of freedom in the eyes of so many has kept them here. For "Nightline," Byron Pitts in New York.
This transcript has been automatically generated and may not be 100% accurate.