Alexei Navalny combines two qualities that Russians admire: a mordant sarcasm toward the country’s leaders and great personal bravery. Together, they make him the most potent political threat that President Vladimir Putin has ever faced.

Navalny’s latest riposte is a wickedly funny video posted Jan. 19 on YouTube, documenting the corruption that surrounds what he calls “Putin’s Palace,” a billion-dollar project on the Black Sea that includes mansions, vineyards, a private casino, even an underground hockey rink. The video alleges a network of payoffs for Putin’s friends and family, as well as for two girlfriends and their relatives.

The mocking video had been seen by more than 90 million people as of Tuesday. And its message of defiance helped bring thousands of protesters onto the streets last weekend in 100 Russian cities to protest Putin’s corrupt and authoritarian regime. Russian security forces arrested more than 3,000 protesters Saturday, and Putin on Monday denied that he owned the “palace.” But his aura of invulnerability has been cracked.

Navalny showed his courage by traveling back to Russia on Jan. 17 from Germany, where he had been recuperating from an assassination attempt that he says was organized by Putin’s security service, the FSB. Navalny decided to release the video only after he had come home. When he arrived at the Moscow airport, he was immediately arrested and taken to prison. Two days later, the video appeared on YouTube.

“We came up with this investigation [of the palace] while I was in intensive care, but we immediately agreed that we would release it when I returned home to Russia, to Moscow, because we do not want the main character of this film [Putin] to think we are afraid of him and that I will tell about his worst secret while I am abroad,” Navalny says in a haunting introduction to the video.

Leonid Volkov, the manager of Navalny’s 2018 presidential campaign and his chief of staff, spoke with me Tuesday in a telephone interview from Lithuania. He said the goal of Navalny’s movement is to make Russia “a normal European country with rule of law and independent courts and free media.” Navalny should be released, and Putin, who extended his term as president through a special constitutional amendment, should “talk about transition of power,” Volkov demanded.

Navalny’s battle with Putin presents an early test for President Biden and his foreign policy team. The new administration immediately called for Navalny’s release. But Volkov argued that the United States should do more, working with European countries to identify and freeze assets held outside Russia for Putin’s benefit. Biden’s press secretary, Jen Psaki, said Biden discussed Navalny and other issues with Putin in a phone call Tuesday, but she didn’t provide details.

Putin’s opulent Black Sea retreat was first exposed by a whistleblower named Sergey Kolesnikov, in an open letter to then-President Dmitry Medvedev, which I revealed in a Dec. 23, 2010, column. Kolesnikov explained that the palatial estate had been paid for by contributions from Russian oligarchs gathered by a St. Petersburg business crony of Putin’s. The money was channeled through a medical supply business that Kolesnikov ran. He told me that, for eight years, he provided regular summaries for Putin about his investments, through the St. Petersburg businessman.

In the new video, Navalny interviews Kolesnikov, who confirms on camera the story that he told me 10 years ago. What’s amazing is that even after the Black Sea estate was revealed back then, Putin’s pals allegedly continued to shovel money into the complex. Navalny said the value of the complex was more than $1 billion and called it “the world’s biggest bribe.”

Using architectural designs, invoices, drone footage and 3-D visualizations, Navalny offers a hilariously scathing account of the palace built for Putin’s pleasure: In addition to the gambling den and hockey rink, it has a hookah bar, a stage with a stripper’s pole and an ornate toilet-paper holder that cost more than $1,200.

Navalny also describes payments made to the families of two women he says were romantically involved with Putin, who is divorced from his wife, Lyudmila. He quotes a well-known Russian folk song that he says applies to Putin: “Three wives are wonderful, what can you say, but on the other hand — I’ve got three mothers-in-law.”

This combination of sarcasm and political outrage is what drives Navalny’s movement and seems to give it resonance with Russians. In the video, he quotes the novelist Leo Tolstoy: “The villains who robbed the people gathered together, recruited soldiers and judges to guard their orgy, and are feasting.”

Navalny now sits in prison. But his words at the end of the video echo across Russia: “The future is in our hands. Do not be silent. Don’t agree to obey the feasting villains.”

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