The women who make it and the ones who don't.

"My name is Rahaf Mohammed. I'm 18 years old... They have my passport and tomorrow they will force me to go back...Please help me. They will kill me." Rahaf Al Qunun.

It was a voice of desperation, an urgent SOS to the world. A Saudi teenager, trapped in transit, on the run from her family and the Saudi state, hoping to make it to Australia.

"I planned my escape...I planned it at dawn, paid for my tickets, left in the morning while my family slept and arrived at the airport." Rahaf Al Qunun.

Within hours #saverahaf lit up social media and set off global headlines.

"There was no going back for Rahaf now...I couldn't live with myself if this was a real person and I didn't do what I could to help her." Author.

Four Corners reporter Sophie McNeill flew to Bangkok, slipped past security and joined Rahaf Al Qunun as the young woman barricaded herself inside the room.

"An official...has just knocked on the door and tried to get Rahaf to leave, she's refused... they've tried all sorts of ways of enticing her out of the room." Sophie McNeill, reporter.

On Monday Four Corners reveals how the extraordinary events unfolded, using exclusive previously unseen video recorded by both Sophie McNeill and Rahaf herself. The program captures moments of high tension, despair and eventual jubilation when Rahaf is offered asylum in Canada.

Rahaf is one of the lucky ones; not every woman gains her freedom. In this dramatic investigation, Four Corners reveals how Australia has become a hotspot for women attempting to escape the oppressive Saudi regime. Not everyone makes it.

"They beat her. They taped her mouth shut. They bound her arms and legs together, and dragged her onto a plane kicking and screaming, and nobody did anything. This is a grown woman." Author.

The program shows the tactics used and the pressure applied to try to stop these young women.

"The Saudi state is active in exerting its diplomatic influence to try to interdict them." Human rights investigator.

Those lucky enough to make it to Australia say they are still at risk. The investigation has uncovered multiple cases of Saudi women here in Australia, living in fear, telling reporter Sophie McNeill of the attempts to intimidate or trick them into returning them home.

"They are trying to reach the girls and speak to them to convince them to return back to Saudi." Saudi woman in Australia.

Escape from Saudi, reported by Sophie McNeill and presented by Sarah Ferguson.

"I'm a hired gun to help either large corporates or governments to get back what is rightfully theirs." Asset recovery agent.

As China has transformed itself into an economic powerhouse, billions of dollars have been illegally spirited out of the country. A large amount has made its way here to Australia.

"I think it's been well understood for a number years that Australia has been a target location for hot money... We've seen that activity increase exponentially over the last number of years." Financial crimes investigator.

Chinese authorities want the money back, and they've sent a clear message to anyone who has broken their rules - we will find you and your money.

"It seems as if there's more than enough evidence that at least in jurisdictions like...Australia, the US and America, coercive tactics were used to force people back to China." Transnational crime expert.

Now China has opened up a new front in its war on those accused of financial crimes. On Monday Four Corners will reveal the new tactics being used by Chinese authorities to take back money they believe has been stashed illegally in Australia.

"The mission is a recovery of funds that have been filtered from China to Australia." Private investigator.

A new breed of financial bounty hunters is on the case, and their target is Australian real estate.

"There's what we're referring to as a cluster of properties... Most of them, or all of them waterfront, luxuriously appointed." Security consultant.

With exclusive access to these investigators, reporter Mark Willacy sees first hand the extraordinary lengths they are going to.

"We can sell it and return the money back to China. Everyone's happy...it's a legal plan. There's no drama." Private investigator.

With questions being asked about the legality of their actions and the reach of the Chinese state, it's a high risk operation.

"I think they have to tread carefully. One of the challenges they've got is that they need to walk a very, very narrow line." Financial crimes investigator.

For the recovery agents themselves, they believe they are onto a financial winner.

"There's a huge opportunity to develop and exploit this business channel, especially when it comes to Chinese money of dubious origin that has parked itself in Australia." Asset recovery agent.