Saudi Prince Alwaleed bin Talal, one of the world’s richest men, knows a thing or two about luxury hotels. He owns the Savoy, in London, and a big chunk of the Plaza Hotel, in New York, (as well as a stake in the Plaza’s condominiums.) Together with Bill Gates, the co-founder of Microsoft, he owns the Four Seasons Hotels and Resorts Company. He also owns the George V, in Paris. He bought it in 1996 for $175 million and spent another $125 million renovating it. He has since boasted to me that it is worth $1.5 billion. When I interviewed Alwaleed a few years ago for a profile in Vanity Fair, we met for the first time in the lobby of the Plaza, half of which he had commandeered for his considerable entourage. His gorgeous fourth wife, whom he has since divorced, was there, too, with her entourage. The second time we met was in the lobby of the George V. He was in command there, too.

Unfortunately for Prince Alwaleed, whose net worth is around $20 billion these days, one of the luxury hotel chains he does not have an ownership stake in, the Ritz-Carlton, is where he has been holed up in Riyadh against his will since Saturday, under house arrest, as part of Saudi Crown Prince Mohammed bin Salman’s sweeping (and shocking) power grab. Alwaleed is one of 11 Saudi princes, four ministers, and many other former ministers, who have been ordered arrested under the guise of the anti-corruption campaign. According to Reuters, he has been charged with money laundering, bribery, and extortion. “The homeland will not exist unless corruption is uprooted and the corrupt are held accountable,” Saudi King Salman decreed on Saturday before appointing his favorite son to head up an anti-corruption task force, which then ordered the arrests.

Alwaleed is a man who likes his creature comforts, and no matter how appointed the Ritz-Carlton in Riyadh may be—“lush with 600-year-old olive trees, landscaped gardens, and swaying palms,” according to company literature—he is unlikely to be very happy being kept there against his will. (Marriott International owns Ritz-Carlton.) Alwaleed, after all, is the founder and 95 percent shareholder of the publicly traded Kingdom Holding, a Riyadh-based investment holding company that he likens to Warren Buffett’s Omaha-based Berkshire Hathaway. (Alwaleed is not shy about comparing himself to Buffett). Kingdom Holding is in the process of building a $20 billion real-estate development in Jeddah, including the Jeddah Tower, slated to be the world’s tallest building. Otherwise, his holdings are notoriously opaque, and often difficult to verify; but, according to his website he claims he is the largest single foreign investor in the United States. (Short of owning a 5 percent stake in a public company, as per the S.E.C. requirement, Alwaleed is not obliged to disclose what he owns.) At times, he has been the single largest investor in Citigroup and second largest investor, after Rupert Murdoch, in News Corporation. It is believed, according to an interview he gave to CNBC last month, that he still owns stakes in Citigroup, as well as 21st Century Fox, which was spun out of News Corporation, as well as meaningful stakes in Twitter, Apple, Disney, and Motorola. He may, or may not, still own equity stakes in Time Warner, eBay, and Euro Disney, which he once rescued from bankruptcy. Alwaleed confirmed on CNBC last month that he still owns Citigroup, 21st Century Fox, Twitter, and JD.com, a Chinese Internet commerce company.

Alwaleed is also opaque about the magnitude of his personal wealth. Four years ago, he told me he was worth $29 billion, which is what the Bloomberg Billionaires Index pegged his net worth at then. But that was just as he was engaging in a public battle of wills against Forbes, which he felt underestimated his wealth by some $10 billion. Since his arrest, Bloomberg calculates his net worth at $20 billion, Forbes has him pegged at $16.7 billion. The small public float of Kingdom Holding has fallen more than 10 percent since his arrest became publicly known.

In any event, Alwaleed is still enormously wealthy, and he enjoys his toys. “What I say is, ‘I live happily,’” he once told an interviewer. (He told me he’d like to one day be the world’s richest man. “Number one is nice, yes,” he said. “I have to be honest with you. Number one is beautiful.”) He wasn’t being insincere. His gargantuan mansion in Riyadh is an eye-popping 460,000 square feet and cost him $130 million. It has 371 rooms, an 80-foot-high entrance hall, 500 televisions and a staff of 100. Fresh flowers are flown in from Holland and the guest bathrooms have gold fixtures. His “country resort” on the outskirts of Riyadh, dubbed “Kingdom Resort,” sits on 250 acres and has a private zoo and an underground cavern. His fleet of cars is said to number more than 300, and it includes Rolls-Royces, Porsches, and Lamborghinis. For security reasons, many of the cars are carbon copies of one another so when he travels around town, one car can be a decoy. He also has a fleet of jets, including a private Boeing 747—outfitted with items you’d expect at a five-star hotel, as well as a gold throne—and a Hawker Siddeley 125, which the first Saudi woman pilot has been trained to fly. He told me that he is the only person with his own 747 (aside from the president of the United States). His 280-foot yacht, Kingdom 5KR, was once owned by Donald Trump, and originally built for Adnan Khashoggi, the Saudi arms dealer. (Alwaleed had reportedly ordered a new, 557-foot yacht, said to cost more than $500 million.)

Trump and Alwaleed have been frenemies for years. In addition to helping to bail out Trump in the early 1990s by buying his yacht, he also helped him again when he bought half the Plaza Hotel, which relieved Trump of imminent debt payments. But the two men don’t seem to like each other much and, not surprisingly, have taken their disputes to Twitter. In December 2015, after then-candidate Trump called for a ban on Muslims entering the United States, Alwaleed tweeted, “You are a disgrace not only to the GOP but to all America. Withdraw from the U.S presidential race as you will never win.” Trump responded: “Dopey Prince @Alwaleed_Talal wants to control our U.S. politicians with daddy’s money. Can’t do it when I get elected. #Trump2016.” A month later, after Trump re-tweeted a doctored photo of Alwaleed with Megyn Kelly, the prince tweeted at him, “Trump: You base your statements on photoshopped pics? I bailed you out twice; a 3rd time, maybe?” After Trump was elected, Alwaleed softened his tone and tweeted his congratulations: “President elect @realDonaldTrump whatever the past differences, America has spoken, congratulations & best wishes for your presidency.”

Notably, Trump’s son-in-law, Jared Kushner, is buddies with the crown prince and recently visited the country. The crown prince’s power grab came just a week or so after the Saudis invited powerful businessmen and selected members of the media from around the world to Riyadh to celebrate what was meant to be a combination of elaborate ring-kissing and the heralding of a new openness for the Saudis on the world stage. How Saturday’s arrests will affect that bit of theater in the desert is not known either.

One thing is clear, though. Alwaleed was at the forefront of trying to push political and cultural reform in Saudi Arabia. He was a leading proponent of the right of women to drive and to pilot jets. He employs many women at Kingdom Holding as business executives. He has been an outspoken advocate of women not having to wear a veil when they go out of the house. “Some people hate me,” he told me at the Plaza. “They hate me for sure. Because they say, ‘What you’re doing is wrong. Ladies should be in the kitchen only. She should only be cooking for her children. Put her under a tent, the veil, to go out.’ That’s not right.”

In an op-ed he wrote in The Wall Street Journal around the same time as our New York visit, he took his reform advocacy even further. The so-called Arab Spring was in the air, and Alwaleed was hoping it would be the start of something big. “If there is a lesson to be learned from the Arab Spring, it is that the winds of change that are now blowing in the Middle East will eventually reach every Arab state,” he wrote. “Now is therefore an opportune time, particularly for the Arab monarchical regimes”—for instance, Saudi Arabia’s—“which still enjoy a considerable measure of public goodwill and legitimacy, to begin adopting measures that will bring about greater participation of the citizenry in their countries’ political life.”

The promise of the Arab Spring petered out, of course, and now it appears that for all his wealth and influence in Western power centers and in Western corporations, Prince Alwaleed’s message of hope and change may be snuffed out as well. The Saudi regime is looking more and more tyrannical. It all overlaps neatly, and scarily, with Trump, who demands absolute loyalty from his Cabinet and his staff, and who wishes the Justice Department were more obedient to him. He’s even taken to claiming sole responsibility for the soaring stock market, the low unemployment rate, and the slight increases in G.D.P. because you know, he’s such a good businessman and so intelligent. We can only hope that Trump’s counterparts in the inner sanctums of the American government aren’t swayed by his public displays of regression and dictatorship fever dreams.