In November, the Saudi government locked up hundreds of influential businessmen - many of them members of the royal family - in the Riyadh Ritz-Carlton in what it called an anti-corruption campaign. Most have since been released but they are hardly free. During months of captivity, many were subject to coercion and physical abuse. In the early days of the crackdown, at least 17 detainees were hospitalized for physical abuse and one later died in custody with a neck that appeared twisted, a badly swollen body and other signs of abuse, according to a person who saw the body. To leave the Ritz, many of the detainees not only surrendered huge sums of money, but also signed over to the government control of precious real estate and shares of their companies - all outside any clear legal process. As the architect of the crackdown, Crown Prince Mohammed bin Salman prepares to travel to the United States this month to court American investment. Saudi officials are spotlighting his reforms. But extensive interviews with Saudi officials, members of the royal family, and relatives, advisers and associates of the detainees revealed a murkier, coercive operation, marked by cases of physical abuse, which transferred billions of dollars in private wealth to the crown prince's control. The government ... has refused to specify the charges against individuals and, even after they were released, to clarify who was found guilty or innocent, making it impossible to know how much the process was driven by personal score settling.