The cyber criminals breaking hearts and stealing billions."The criminals involved in this are definitely masters of manipulation. This is their job and they're very good at it, and they're very proud of being good at it." Cyber scam expert.Their voices are persuasive, their emails insistent and they have proven to be remarkably successful at conning countless people into handing over their money."When you have an appreciation for how big and sophisticated it is, this machine that's behind it that's targeting them, that's where it sorts of tends to awaken one." Police officer.Internet scamming began in the early days of email with appeals from Nigerian 'princes' asking for help to regain their missing money. From those amateurish beginnings, the scammers watched, learned and refined their techniques. What started out as a simple scam from West Africa has now morphed into a global enterprise, conning people on an industrial scale."West African cybercrime is the biggest threat that we see on the internet today. It eclipses all the other threats that we've seen that are financially motivated." Cyber security investigator.On Monday Four Corners investigates how these scams operate, uncovering an online marketplace where fake identities and criminal skills are bought and sold."They offer Facebook profiles for sale, they offer pictures of uniformed servicemen for sale, they offer the backstory and kind of how you get started." Retired US army colonel.Reporter Sean Rubinsztein-Dunlop travelled to Ghana to meet the scammers and watch them at work."The best targets are people who are divorced or widowed." Scammer.At the heart of their business is the 'romance scam', where criminals, often posing as lovelorn US soldiers, convince their victims to send them money."Over the course of the last two years, I've reported over 3,000 accounts to Facebook of scammers using my pictures to steal money from women." Retired US army colonel.For some, the romance scam is just the start of the nightmare, with victims used to launder money or conned into trafficking drugs, with devastating consequences."When they opened it and tested it and told me what it was, I was in complete shock, complete shock." Drug mule.And there's growing evidence that the scammers are not only targeting Australian victims, they're also setting up operations right here.Meet the scammers, reported by Sean Rubinsztein-Dunlop.