A General climate of fear: shadows lengthen from the Kremlin.

RUSSIA is once again becoming the country it has always been, where the will of the ruler in the Kremlin is the supreme law. President Vladimir Putin is drawing a line under the Gorbachev-Yeltsin era of comparative democracy. In foreign and domestic policies, Putin has been concentrating power into his own hands. The Federal Security Service, or FSB in its Russian acronym, has simply taken over from its predecessor, the KGB, as the arm of state to make sure the ruler has his way. Putin's term of office ends next year, but yes-men are already proposing to change the constitution in order to extend his presidency.

Elimination of rival claimants to power testifies to this reversion to the past. The lucky ones are able to escape into exile abroad. One such is Boris Berezovsky. Once preeminent among the nouveaux riches oligarchs, he used to be a crony of Putin's, on whose behalf he acted as a powerbroker. Making his own ambitions too plain, he condemned himself to flight.

In order to break the independence of the huge oil company Yukos, its head was put through a show trial and deported to Siberia; and his deputy was put in a penal colony. Bankers, journalists, businessmen, or even oil technicians are murdered when they venture into public life. Since these killings are neither prevented nor properly resolved, the man in the street attributes them to the Kremlin and the FSB. A general climate of fear takes hold.

Freedom of expression was one of the main Gorbachev-Yeltsin achievements, but it is now almost entirely under state control. No fewer than 14 journalists have been killed since Putin took office in 2000, and police investigations vanish into thin air. One typical victim was the Russian-American Paul Klebnikov, shot dead in the street by persons unknown. The FSB likes to pin this crime on Berezovsky, about whom Klebnikov had published a muckraking (and, in many respects, probably truthful) book with the title Godfather of the Kremlin. Anna Politkovskaya, one of Russia's leading reporters, wrote books and numerous articles to expose brutalities in the war against the Chechens, for which she held Putin responsible. She too was shot dead in her apartment block. The killer was filmed on closed-circuit television but has not been identified or arrested. Ivan Safronov, the most recent journalist victim, had been researching sales of Russian missiles to Iran. He lived on the second floor, but was found to have fallen from a window on the fourth floor. His editor is sure it was murder.

Even against this background of suspicion, intimidation, double-crossing, and violence, the death in London last November of Alexander Litvinenko is extraordinary, and will remain a landmark in the annals of crime. For a start, the murder weapon was a novelty, polonium-210, otherwise used only in initiating nuclear weapons. Once ingested, a very small amount is enough to bring bodily functions to a halt. It should work immediately, so fast that the cause of death is a mystery. A particularly fit man, Litvinenko survived long enough for experts to identify the poison. On his deathbed, a tragic and spectral figure who had gone bald and aged prematurely, he wrote an open letter accusing Putin of responsibility for his murder.

Future thriller writers and conspiracy theorists will be taking an interest in the case. Four books are apparently being written already, and Hollywood is planning a movie. Suspects and clues already exist in the world of nonfiction, however. Two ex-KGB agents, Andrei Lugovoi and Dmitri Kovtun, admit to meeting Litvinenko on the day the polonium was administered, and in a hotel bar ideal for the purpose. Moreover, a giveaway polonium trail is traceable in rooms they slept in or visited, and in aircraft they flew on. They claim to be innocent. Kremlin spokesmen, as well as Putin, either sound indignant on their behalf or dismiss Litvinenko as a nonentity. Seemingly protective of the chief suspects, the Russian foreign minister, the prosecutor, and the police authorities combine to impose conditions that block investigation and possible extradition to Britain.

British scientists meanwhile have been able to establish which Russian-government power station produced the polonium. The state is the sole producer, and the costs would have been on the order of $10 million. The polonium can only have been handed out for use officially, or stolen. Scotland Yard detectives have been to Russia and believe they know who did what and when, but they are not saying anything, and perhaps never will.

Like the two men suspected of killing him, Litvinenko was an ex-KGB officer, with the rank of lieutenant colonel. His story was that he had been ordered to kill Berezovsky when Putin finally fell out with the oligarch. Rather than do so, he informed Berezovsky. Paul Klebnikov writes in his book that this was all a fabrication, but at any rate both Berezovsky and Litvinenko ended up in exile in London. There they became friends and associates. Berezovsky is said to have bought the London house in which Litvinenko and his wife Marina lived, and to have financed him as an investigative journalist. Primarily, Litvinenko exposed the barbarity of Russian tactics against the Chechens--the bulk of his work was put out on Chechen websites. With a colleague, Yuri Felshtinsky, he wrote a book, Blowing Up Russia, whose thesis is that the FSB bombed houses in Russia proper only to have a pretext for assaulting Chechnya. Litvinenko further personalized his attacks by describing Putin as a pedophile.

The post-Communist community of Russian exiles in Britain ranges from super-rich oligarchs to intellectuals of the stature of Vladimir Bukovsky, the former dissident. Their doyen, Oleg Gordievsky, occupies a position of preeminence much as Alexander Herzen, the great liberal and critic of czarism, did in the 19th century. A career officer in the KGB, Gordievsky was at the center of totalitarianism in action but refused to participate. Becoming a double agent, he worked with British intelligence until in 1985 he was detected and had to be smuggled to safety. To the KGB, he was a traitor, and condemned to death.

Sixty-eight now, Gordievsky lives carefully. The expression on his strong face is hard to read, though he says what he thinks shortly and directly. Any media outlet that publishes an apology for Communism or the Soviet Union is virtually certain to receive a sharp letter of reprimand from him. While I was in his house, the telephone rang a good few times, and lengthy conversations in Russian followed. Russian media ask for interviews, but these he refuses to grant.

Bukovsky introduced Litvinenko to Gordievsky, saying that Litvinenko had amazing information to impart. Litvinenko visited Gordievsky quite often, and they used to lunch together in pleasant local restaurants. Litvinenko drank only tea or Coke. He appeared lonely. No cosmopolitan, he remained attached to Russia, and besides, his English was not good. Nonetheless he had become a British citizen. He believed he was threatened, but still he used to walk to Berezovsky's office in central London and go home on foot by himself through nearby Hyde Park at midnight. Active and athletic, he was fearless. He and Berezovsky trusted each other.

A Russian team of police, legal advisers, and interpreters has just been in Britain. They arrived with a list of a hundred people they wanted to see. Gordievsky dismisses this as "total bluff." Theirs was a sham investigation. The FSB disinformation and misinformation services, he says, "are working day and night to invent new lies. I know their methods." They questioned only two people, one of whom was Akhmad Zakayev, the prominent Chechen exile and "a lovely chap," in Gordievsky's anglicized phrase. The other person they interviewed was Berezovsky, whom the Kremlin is assiduously trying to frame for Litvinenko's murder: "And for once he was very good. He isn't always. He told them they should be ashamed of themselves." Berezovsky has to be "terminated" because he helped Putin reach the top and knows too much. "He's a living witness that an oligarch got him elected president." It infuriates Gordievsky to read in the British press that "rogue elements in the FSB" carried out the murder behind Putin's back. The system prevents any possibility of it, and besides there are no such rogue elements.

Russians ought to rise in protest, Gordievsky says, but they just want a good salary and perks. Communism killed off everyone capable of independent thought. Putin is taking whatever he can from the past to rebuild a totalitarian society, and yet Russia is tolerated by everyone rather than treated like Belarus, to be cold-shouldered and excluded from organizations like the G8. Gordievsky's friends in British intelligence assure him that Scotland Yard will eventually bring the Litvinenko murder to court, but he is expecting a cover-up. Almost his last words as I left the house were "I don't know how to express my indignation."

Mr. Pryce-Jones, an NR senior editor, is the author of some 25 books, including The Strange Death of the Soviet Empire.