In anticipation of the upcoming fourth season of our HBO show which will premiere this February, we are releasing all of season three for free online. Watch all the episodes here, and don't miss the premiere of season four on Friday, February 5, at 11PM on HBO.Over the course of one week last spring, more than 100 teenagers in Dallas overdosed on a drug called K2. In August, the governor of New Hampshire declared a state of emergency after 44 overdoses were linked to the bubblegum flavor of a drug called "Smacked." This is the world of synthetic drugs, manmade chemical compounds often engineered to skirt narcotics laws—and some of the most frequently abused substances in American high schools.The makers of these drugs race to keep ahead of law enforcement by making incremental changes in the compounds' molecular structure, even though the effects of those alterations can turn out to be dangerous.In this episode from season three of our HBO show, VICE correspondent Hamilton Morris tracked these chemicals back to the Chinese factories where many are made and met the godfather of modern synthetic drugs at his remote lab in New Zealand.In our second segment, VICE followed the stories of homosexuals and transsexuals in Iran as they navigate the country's terrifying cultural landscape.