When we think about the global heroin trade, the news is usually about Mexican cartels and North American opioid crisis. In fact, the country seizing more heroin and opium than any other is usually the Islamic Republic of Iran. Despite being an authoritarian, religiously puritanical state that even bans alcohol, drug addiction has spread like wildfire across Iranian society. This is how a combination of geography, geo-politics and failed War on Drugs policies in Iran have created what might be the world’s worst heroin crisis – and how corrupt elements of the Iranian state itself might be profiting from it.