Fentanyl can be a confusing drug. Not only is its name often mispronounced (it's "fentan-ill"), but it's just hard to conceive of a drug so strong that a little bit can kill.
And it does; fentanyl figured in the deaths of Tom Petty and Prince, and kills thousands of lesser-known people every year.
Why IS there a drug roughly 50 times stronger than morphine and heroin? These are among the questions researched by Ben Westhoff in the book Fentanyl, Inc.: How Rogue Chemists Are Creating the Deadliest Wave of the Opioid Epidemic. The research included visiting a fentanyl lab in China. The author visits with details of the drug and what he found out about it.