Book excerpt: A new cultural icon strode the world stage at the turn of the twenty-first century: the celebrity scientist, as comfortable in Vanity Fair and Vogue as Smithsonian. Declan Fahy profiles eight of these eloquent, controversial, and compelling sellers of science to investigate how they achieved celebrity in the United States and internationally—and explores how their ideas influence our understanding of the world. Fahy traces the career trajectories of Richard Dawkins, Stephen Hawking, Steven Pinker, Neil deGrasse Tyson, Brian Greene, Stephen Jay Gould, Susan Greenfield, and James Lovelock. He demonstrates how each scientist embraced the power of promotion and popularization to stimulate thinking, impact policy, influence research, drive controversies, and mobilize social movements. He also considers critical claims that they speak beyond their expertise and for personal gain. The result is a fascinating look into how celebrity scientists help determine what it means to be human, the nature of reality, and how to prepare for society’s uncertain future.