By nearly all accounts, Rio de Janeiro’s Summer Olympics were not as bad as they could have been. In spite of green pool water, Ryan Lochte’s lies, and terrible American TV ratings, there were a lot of people who made a lot of money. Brazillionaires, a recent journalistic account of Brazil’s billionaire class, is a capable and thorough examination of the kinds of Brazilians who profited from the Games. The book chronicles the accumulation, entrenchment, maintenance, and expansion of the country’s largest fortunes and business empires.