Fentanyl is a first-person, insider account of how the crisis consumed the Biden Administration amid a series of other national security emergencies. It follows Jake Braun, a senior White House official, and his colleagues while they scramble to respond to the epidemic. As Mexican cartels ruthlessly executed their most radical transformation in 50 years, Braun and his colleagues architected the first U.S. government wide strategy to combat fentanyl in history. The effort brought him to Mexico to meet with Mexican agents who kick down cartel doors for the U.S. government there. He also spent time with data analytics wizards buried in nondescript offices in Virginia suburbs that hunt down Chinese fentanyl precursor chemicals on the Dark Web. He even takes a detour to gather intelligence from Russian migrants in U.S. detention facilities that migrated through cartel-controlled areas of Mexico. In the process, Braun uncovered the remarkable transformation cartels in Mexico underwent over the last 50 years. They morphed from narco-empires the size of Fortune 50 companies specializing in marijuana and cocaine to ones specializing in human migration and, separately, fentanyl. After much painstaking effort, the Biden Administration successfully executed the most sweeping takedown of cartel leadership and fentanyl infrastructure since the crisis began. Due to the efforts of heroic agents, intelligence officers and national security experts, the leviathan U.S. government is now marshaled in ways never before imagined against the Chinese chemical companies and cartels propagating the fentanyl epidemic. Further, the strategy seems to be working. Just a year after it was kicked off, the fentanyl fatalities dropped nearly 37%. Yet the crisis persists. Finally, Braun draws on his unique experience combating the epidemic to outline how the U.S. government can once and for all end the fentanyl crisis in America.