Paper Chase.

Archangel, by Robert Harris (Random House, 373 pp., $24.95)

Prospective readers should not be put off if the reviews say that Robert Harris's Archangel carries an important political message and that the author's own political position is interesting. Rest assured, we have here an exceptionally well written, skillfully crafted, continuously gripping thriller. "Unputdownable," as publishers used to claim.

It begins in Moscow-garish, dangerous present-day Moscow, still resonant with echoes of its equally ruthless but more self-confident Soviet past. C. R. A. "Fluke" Kelso, an English historian whose life and career have begun to slide, is lured by the possibility of a great professional prize-finding Stalin's private journal, which is thought to have been stolen and hidden at the time of the dictator's death. As he pursues the tantalizing hints through dusty archives and derelict buildings, Kelso is urged on by an unscrupulous American television reporter, R. J. O'Brian. They become aware of being watched and followed; they are not the only ones looking for the lost notebook. There is a murder. They embark on a foolhardy journey north, where, amid the vast snowbound forests, deadly traps and a fearsome revelation await them.

The sinewy plot never slackens, but what makes the book memorable are the vividly observed backgrounds-crumbling, haunted urban Moscow and a deserted hinterland that can swallow men up. No less authentic are the fragmented but undead relics of the old Soviet system, not least the secret police, which has kept reincarnating itself, as the Cheka, the OGPU, the NKVD, the KGB, and now the SVR (spies) and the FSB (internal security). Looming like an iceberg are the archives, now in theory open for inspection but in fact mainly still censored or locked away.

Which brings us, unavoidably, to politics. About the contemporary politics of his own country, England, Robert Harris is deeply and sometimes almost hysterically leftist. On politics of the past he is more sound. The target of his best-known previous book, Fatherland, was Hitler's Germany. The dramas of history in general fascinate him. The protagonist of Archangel clearly represents the author: "He could feel the charge of history in the dark and renamed streets, the vast apartment blocks, the toppled statues. It was stronger here than anywhere he knew, stronger even than in Berlin. That was what always drew him back to Moscow-the way history hung in the air like sulfur after a lightning strike."

Here, and in articles and interviews, Harris says bluntly that Stalin was a worse monster than Hitler and that the specter of a revived Marxism is far more threatening than the turnip ghosts of neo-Nazism. Marxism has never been properly purged from the world's blood-system. Western celebrities and Third World politicians cheerfully acknowledge their Communist past. They would be much less ready to admit that they had once belonged to the Hitler Youth Movement. Academia remains full of Marxist professors: How many would obtain tenure if they were as openly Fascists? In Russia, nostalgia for the old days, even for Stalin himself, is widespread. In the most recent Duma elections, 30 percent of the vote went to Communists, in the 1996 presidential election, 40 percent. Archangel's Kelso ponders a poll result showing that one in six Russians-about 20 million people-believe Stalin to have been their greatest ruler. "The sainted Lenin, of course, had even more support. . . . If one in six Germans had said they thought Hitler was the greatest leader they'd ever had, the New York Times wouldn't just have wanted an op-ed piece. They'd have put it on the front page."

Harris's picture of Stalin, a collage of chilling details, almost ungraspable statistics, and lurid recollections from those who knew him, is as effective as anything since Robert Conquest showed an apathetic Western public the enormity of the crimes involved. We are given brief glimpses of the terror that paralyzed Stalin's colleagues, of the way in which so many of those closest to him disappeared, of the long death- lists, including the names of old comrades, signed without a qualm.

Harris said in a television interview that he was more obsessed with Stalin than he ever had been with Hitler. Modern Moscow, where tapes of Stalin's speeches are sold on street corners, is very different from today's Germany-but perhaps not so different from yesterday's. "It's the Weimar Republic," says the American reporter to Kelso. "All we need is Marlene Dietrich in a tuxedo, and we might as well be in Berlin."

Archangel is chiefly a very good story; but novels, as Harris demonstrates, can sometimes bring out truths that history books cannot. Only a few weeks ago the Russian Duma voted, 237 to 69, that a huge statue of Feliks Dzerzhinsky, head of the Cheka and the OGPU, and the creator of the whole apparatus of state terror, should be restored to its place in Lubyanka Square. The FSB, still based in the Lubyanka, took up a collection to help pay for its return. If the German parliament had voted overwhelmingly to erect a giant statue of Himmler outside what used to be Gestapo headquarters, would the Western press not have paid rather more attention?

Mr. Lejeune is NR's London correspondent.