In the history of U.S. politics, few meteors have burned as hot or hit as hard as Steve Bannon, the fiery provocateur behind Donald Trump’s transgressive and unexpectedly successful 2016 campaign for the White House. Bannon, who prior to the campaign had been largely unknown beyond the audience of his controversial “alt-right” website, Breitbart News, helped Trump skewer the bipartisan political establishment and activate enough angry voters in the right places to eke out an Electoral College victory despite losing the popular vote. Green saw Bannon as an important figure early on and began to track his career long before other journalists. As a result, Green had the material and access to produce a deeply researched and sharply observed account of a political figure and a movement that took most of the country by surprise. Many seasoned observers thought that Trump had rendered himself unelectable by embracing and peddling “birther” conspiracy theories regarding President Barack Obama’s national origins. Bannon, however, understood that Trump had forged a bond with a significant Republican constituency that could win him the GOP nomination and put him on the road to the White House. Although Bannon’s tenure as Trump’s chief strategist in the White House was brief and mostly unsuccessful, it is unlikely that his influence in U.S. politics will fade quietly away. Readers will find no better guide to Bannon’s vision than this gripping and sometimes appalling account.