An undercover investigation into the synthetic-drug epidemic.

A new group of chemicals is radically transforming the recreational-drug landscape. Known as novel psychoactive substances (NPS), they range from so-called 'legal highs' like Spice to synthetic opioids - most famously, the deadly fentanyl.

Designed to replicate the effects of established drugs like cocaine, ecstasy, marijuana, and heroin, NPS is synthesised in laboratories. They are cheap to produce and easy to transport. They are also extremely potent and often deadly. Originally developed for medicinal purposes, and then hijacked by rogue chemists, who change their molecular structures to stay ahead of the law, these chemicals' effects can be impossible to predict. What we do know is that they have triggered the biggest drug epidemic that America has ever seen, and which is now spreading internationally.

In Fentanyl, Inc., award-winning journalist Ben Westhoff goes undercover to investigate the shadowy world of synthetic drugs - becoming, in the process, the first journalist to infiltrate a Chinese fentanyl lab. He tracks down the drug baron in New Zealand who unintentionally helped to start the synthetic-drug revolution; prowls St. Louis streets with a former fentanyl dealer to understand how the epidemic started; and chronicles the lives of addicts and dealers, families of victims, law enforcement officers, and underground drug-awareness organizers in the US and Europe. Fentanyl, Inc. is essential reading on a global calamity we are only just beginning to understand.