When border guards stopped her escape to India, Maheshwori Nepali was furious.

"I felt very angry that they were holding me up and asking me so many questions," she says.

Born into one of Nepal's lowest castes — the Dalits — she was seeking the promise of a better life over the border.

"In my village, we have very severe untouchability stigma," she says.

"We have no access to the higher castes … they do not even go to the well to get water if I've used it.

"Also, there is no work for us."

So when an older family friend offered to take her across the border to study in India at age 19, she jumped at the opportunity.

"This man was known for so many years in my village. The whole family trusted this man," Maheshwori says.

But when she arrived at the checkpoint, suspicious guards stepped in and the plan was sprung.

"If they had not stopped me I would have gone," she says.

As many as 50 women and girls are trafficked into India from Nepal every day. ( ABC News: Zoe Osborne )

Little did Maheshwori know that her new life would begin right there — not as a trafficking victim, but as a border guard with the NGO 3 Angels, rescuing women in the same precarious position she was in.

Driven by desperation

As many as 50 women and girls are trafficked into India from Nepal every day.

They are sold into the sex trade, circuses or massage parlours, used as human bombs or drug mules, or exploited for forced labour.

In some cases, children are even stolen for use in human sacrifices.

"There is a Hindu belief in India that if a huge construction needs to be built it will require a human sacrifice," says 3 Angels co-founder Rajendra Gautam.

Others are trafficked for their body parts, organs, hormones or skin.

"After the organs are taken out, most of the time they will either force the victim to go and beg … or just throw them onto the street," he says.

3 Angels co-founder Rajendra Gautam (left) says the government could prevent a lot of trafficking if they closed the open border. ( ABC News: Zoe Osborne )

But the majority end up in Indian brothels where Nepalese girls are in demand, especially virgins with fair skin and Mongolian features.

In India and some parts of Africa, a Nepalese virgin is widely believed to cure AIDS.

About a quarter of Nepal lives under the international bread line, without access to basic facilities.

When the Ghorka Earthquake struck in 2015, leaving 800,000 houses in ruins, life became even harder.

While caste discrimination is illegal, it is still widely practised.

Lower caste Nepalese like Maheshwori who can't work are forced to find work in other countries.

More than 30 per cent of Nepal's GDP is money sent home by offshore workers.

For many, leaving Nepal can mean the end of their life as they know it. ( ABC News: Zoe Osborne )

No passport or visa is required to enter India and the Indian caste system doesn't discriminate against Nepalese people, so many simply travel south.

All traffickers have to do is pose as employment agents and the victims traffic themselves.

'That's the end of their life'

Traffickers work in a network with varying levels of information.

Trafficker A is a local from a remote village who is keeping tabs on the local women's problems.

"Some may have broken family, some may have a domestic violence issue, some may have drunken parents," Rajendra explains.

"He will be well aware of who is sitting where and then he will go to each person's parents and say, 'look you're having this problem, it's because of the money and I have a big job for your daughter'."

Many of the staff attending this workshop are victims of human trafficking. ( ABC News: Zoe Osborne )

Trafficker A then hands 15 or so girls to Trafficker B for a small return.

Trafficker B, who's based in a bigger city, will hold the 15 girls in captivity, usually in a motel.

This is where the big money comes in, because Trafficker B and Trafficker C, who's stationed at the border, know where the girls are headed.

"Trafficker C hands over the big money and the girls are taken across the border to Trafficker D, who could be an agent representing a brothel from India," Rajendra says.

"The girls are taken across and that's the end of their life."

Escorts usually kept in the dark

Inside the booth at the Sounali crossing on the Nepal-India border. ( ABC News: Zoe Osborne )

Now, from her job on the border, Maheshwori can see the danger she was in.

Her "family friend" has disappeared, but she's convinced she would have been trafficked, like the cases she intercepts every day.

Often the traffickers fight back.

One guard say he receives threatening phone calls and has been pelted by stones on the way to work.

But the guards continue to intercept as many as 10 cases a day at each of the 14 checkpoints along the 1,758-kilometre border.

Maheshwori Nepali stops someone at the Nepal-India border to talk to them. ( ABC News: Zoe Osborne )

"We look for the way people behave," Maheshwori says.

"Often if it's someone who is doing wrong, their facial expression will change when they see us."

But the border is almost impossible to monitor completely, with as many as 100,000 people passing through each checkpoint every day.

If Maheshwori does intercept a potential trafficking case, confirming her suspicions can be difficult.

It is very common for victims to lie about their situation, believing they are going to India for a great opportunity.

Maheshwori recently intercepted five women on a bus who claimed to be going to India for work.

Traffickers in Kathmandu had sent the girls to the border with strips of medicine and hired an escort to help them across the border — a common practice.

"The escort was only told 'please help them to buy more medicine in Delhi'," Maheshwori says.

Like the victims, the escorts are usually kept in the dark.

Maheshwori interviews a woman after stopping her at the border. ( ABC News: Zoe Osborne )

Shifting attitudes towards trafficking victims

The women on the bus Maheshwori rescued were brought to the 3 Angels rehabilitation centre where they work through the trauma of their experience.

Many are exiled from their families because of the stigma of being a trafficking victim.

Radio jockey Pushkar Badi says they try to shift attitudes towards trafficking victims through the outreach program. ( ABC News: Zoe Osborne )

Pushkar Badi, a radio jockey for the 3 Angels radio outreach program, explains why.

"If my daughter or my son is trafficked, my reputation will go down," he says.

"People say, 'see his daughter or son … he couldn't control them'. To save my reputation, I can't accept them."

Through the outreach program, they try to shift attitudes towards trafficking victims.

"When a woman goes to a foreign country they think this lady has done something wrong in the foreign country," Pushkar says.

"People think that she's free now [from parents/husband] she can do whatever she likes, so who knows what she did?

"When a victim is rescued, first of all they want to kill that trafficker, then they want to kill themselves, but mostly they want to go home, but they need their parents' support."

Excommunicated from their families, many victims will return to the trafficking rings in search of work.

3 Angels try to integrate as many victims as possible, either as staff members (including border guards) or as part of their entrepreneur programs, which range from micro-finance loans to a peanut butter factory.

Many trafficked women end up in jail

Pushkar lost his own mother to trafficking as a young boy.

Soon after, his eight-year-old brother also disappeared.

"I haven't seen my brother for almost 13 years," he says.

"Some people say 'your brother is somewhere near to India', some people say 'I have seen your brother over here,' so who shall I believe?"

Arjay was stopped at the Nepal-India border because 3 Angels thought he was trafficking a woman. He wasn't. ( ABC News: Zoe Osborne )

Even if Pushkar's brother were alive, he would probably never be able to come home.

"[Some] people who are trafficked will live the rest of their lives in enslavement," says Mike Newton-Brown, co-founder of NGO The Freedom Project.

"Because they're out of circulation, they don't have rights, they don't have the language. They are not noticed."

Any chance of rescue comes down to the Indian police, but corruption and a lack of education mean they are not always effective.

"The police often see prostitutes as perpetrators, not victims," Mike says.

Many trafficked women end up in jail for doing the work they have been enslaved to do.

Enforcement of anti-trafficking laws in Nepal is also weak. In many cases, officials are involved in the trafficking themselves.

According to Rajendra, if the government simply closed the open border, they would mitigate trafficking by as much as 80 per cent.

"We need the international community … to pressure [the] Nepali government to stop trafficking with strong policies, strong law enforcement," Rajendra says.