Europe has mostly been spared from the synthetic opioid crisis that has ravaged the U.S. over the past two decades. But now, a deadly new drug could be changing that: nitazenes. Up to 15 times stronger than fentanyl, nitazenes have been behind hundreds of overdose deaths in European countries over the past few years. WSJ's Sune Rasmussen on where the drug comes from and why it's doing so much damage. Jessica Mendoza hosts. Further Listening: Fentanyl Is Bad. ‘Tranq’ Might Be Worse. The Push to Test Drugs for Fentanyl Why Some Opioid Victims Are Challenging Purdue’s Settlement Sign up for WSJ’s free What’s News newsletter. Learn more about your ad choices. Visit megaphone.fm/adchoices