Evelyn Chumbow was once a slave, but not in some distant country. She worked right here in the United States.
Chumbow, now 21, was brought to suburban Maryland in 1996 from her native Cameroon by Theresa Mubang. Mubang promised Chumbow's family that if 11-year-old Evelyn came to America, she would have the prospect of a bright future and a first-rate education, as she had been a top student in her native country.
Instead, after she arrived, Mubang enslaved the child in her home, forcing her to work long hours and depriving her of the education she was promised, and never paid her a dime.
In Chumbow's first-ever television interview, she recounted to ABC News how she survived her ordeal and triumphed over the sadistic woman who held her captive.
"When I didn't do what she wanted me to do … she would beat me up," Chumbow said. "And when she get tired of beating me up, she had like pretty long nails and she would scratch me with it, grab me by her nails."
Quite a difference from what she imagined when she watched "The Cosby Show" and "The Fresh Prince of Bel-Air" in Cameroon, and dreamed of becoming a lawyer in the United States. But after she arrived it soon became clear her dream would become a nightmare, as she got caught up in an underground trade that affects thousands of people across the country.
Government estimates say about 15,000 to 18,000 people enter the United States annually to work in deplorable conditions for little or no pay. These men, women and children are ensnared in global human trafficking -- a lucrative and thriving underground trade involving an estimated 800,000 people worldwide every year.
Chumbow is now free and is rebuilding her life while striving to help others, and she said the worst part of her treatment was how Mubang spoke to her.
"All the words that she would say to me would hurt more than the beatings -- like calling me dumb and dirty," she explained. "And that I was not smart and I would never make it, and if she would send me to school she wouldn't know what I would be doing in school."
She found herself asking "why is this happening to me" and looking longingly outside the window as other children boarded a school bus in the morning.
"I was crying. I was like, 'I wish that was me,'" she said. "Those times I would think about running away or just going back home."
"What I would say to the American people is that they have to realize that this happens all over the country, in the backs of restaurants, in the fields in Florida, in the timber industry in the north of New York. There's nowhere in America that it doesn't happen," said Melanie Orhant, Chumbow's former attorney and the managing attorney for the Break the Chain Campaign, an organization that helps trafficking survivors.
Assistant Attorney General Wan Kim, head of the Justice Department's Civil Rights Division, said money drives the thriving human trafficking industry, one of the most lucrative of the underground trades.
"When you ask yourself, how could a human being do this to another human being, there's no good answer to that. But one of the answers is, boy, they're making a lot of money or saving a lot of money by doing that," said Kim.