It was originally hailed as a great way to quit smoking, but now there are serious concerns a new generation of Australians could become hooked on vaping, thanks to a thriving black market on social media. At the same time, big tobacco companies are working behind the scenes to relax laws and increase the use of e-cigarettes. Today, 4 Corners reporter Grace Tobin, on why the industry has gone underground and how cigarette companies are reverting to old tactics. Featured: Grace Tobin, 4 Corners reporter Correction: This story stated that at the time of Juul's testimony Phillip Morris International owned a third of Juul. This was incorrect. The parent company of tobacco giant Phillip Morris USA owned a third of Juul.