WINTER A Novel of a Berlin Family By Len Deighton Knopf. 571 pp. $19.95

IF THERE ARE two fields in which Len Deighton could be said to enjoy a certain expertise, they are modern espionage and military history; and if there is one place that fascinates him, drawing him back time and again like some mist-shrouded city in a dream, it is Berlin, where in this century the baroque worlds of the spy and the soldier have so often converged.

Perhaps in an effort to get back to the roots of this fascination once and for all, even to exorcise it, Len Deighton has in his latest novel abandoned the genre of the spy thriller and undertaken to write, instead, a social and political history of modern Germany, refracted through the prism of a single Berlin family. In the language of the television age, Winter is neither fiction nor history but docudrama, running like a film script in a series of dutifully dated vignettes from New Year's Eve 1899 (birth of "a whole new century") to 1945 ("When the fighting, and its horrendous aftermath, ended, Berlin was like a Hollywood film set . . . a honeycomb of enclosed empty space." Nuremberg serves as prologue and epilogue, the plot calls for scenes in Vienna, Munich, London and New York, but Berlin is at the novel's heart.

Deighton seems to have recognized that the book's status as fiction may be problematic. He goes to the trouble of emphasizing in the prologue that his story is not fiction in the usual sense: "Fiction had unity and style, fiction had a beginning and a proper end, fiction showed evidence of planning and research and usually attempted to impose an orderly pattern upon the chaos of reality. But the lives of the Winter brothers were not orderly and had no discernible pattern . . . Actually, neither {of their lives} was a story at all. Like most people, they had lived through a series of episodes, most of which were frustrating and unsatisfactory."

Yet, one might reasonably ask, if Deighton's fictional equivalent of William L. Shirer's The Rise and Fall of the Third Reich is not going to perform fiction's special task of making sense of the world for us, why shouldn't we just go ahead and read The Rise and Fall of the Third Reich, and enjoy the advantages of footnotes and index?

One answer is that Winter is an altogether silkier, less demanding and more entertaining read -- and entertainment is docudrama's other name. Len Deighton certainly knows how to move a narrative along, build suspense and weave mysteries, even if history did write the larger plot for him.

Central to the story is the Winter family of Berlin, headed by Harald, a coldly intelligent banker and factory-owner (he manufactures aluminum frames for airships, the history of which forms a fascinating sub-plot) and Veronica, ne'e Rensselaer, an aristocratic American expatriate, generous, loving and frustrated. The Winters' two sons, Peter and Pauli, born around the turn of the century, grow up close, become lawyers, but diverge in their political loyalties. Peter, an amateur musician and philosopher, dedicated to democratic principles, winds up a colonel in the U.S. Army. Pauli, quick, kind, but weak, groomed in officer-cadet school, lands a legal job in the Berlin Nazi Party office and eventually rises to a high-level position in the party with the honorary rank of SS-Obersturmbannfuhrer. In their personal relationship, Peter and Pauli thus represent the schism generated in Germany as a whole by Hitler's violent seizure of power. Symbolically, the brothers meet for the last time at the Nuremberg trials, on opposite sides of the courtroom.

Actually everybody in Winter represents something, a social class, a rank, a race, a faith, a profession, a city, even a sibling position, each reacting to the advent of the Nazis pretty much along the lines plotted by sociologically-minded historians. Much is made, for instance, of the connection between Pauli's position as the insecure younger son and his vulnerability to Nazi ideology ("I've always been adaptable: younger brothers have to adapt to what everyone else wants.") Harald Winter remains a capitalist and imperialist, a man of the Kaiserzeit. Peter marries a "Jewish American intellectual," Lottie Danziger, who is trapped in Berlin during the war, thereby creating a conflict for Pauli between loyalty to family and loyalty to party. There are other Jews: a dentist and his family, Harald's illegitimate son in Vienna (representing the Mischlinge or mixed-race Jews). A working-class childhood friend of the brothers is first a socialist in the party of Karl Liebknecht and Rosa Luxemburg, then -- in a switch made by many left-wing extremists in the confusion following Germany's defeat in the First World War -- a Nazi stormtrooper and ultimately a Reichsminister. Pauli's elegant, brainless wife, Inge, on the rebound from Peter, takes comfort in the strong, simplistic answers provided by the Nazis, becoming a prototype of the female Aryan fanatic. And so on.

FANS OF Len Deighton will not be surprised by the snappy pace and variety of the narrative. They will have fun, too, with Deighton's inclusion of several characters whose offspring have central roles in his recent spy trilogy, set in the '80s, Berlin Game, Mexico Set and London Match (here are Bret Rensselaer's grandparents, Bernard Sampson's father, Frank Harrington as his younger self, fresh out of Oxford, and Werner Volkmann, son of the Jewish dentist, still in diapers). It's not clear whether Deighton develops these links between such very different books as a clever way of reinforcing the illusion of "real life" or because that is just the way his imagination works, mining different aspects of a unified fictional world.

It needs to be said, however, that Deighton abandons the conventions of the thriller -- and pure fiction -- at some cost. In The Ipcress File and Funeral in Berlin and The Billion Dollar Brain and SS-GB and Berlin Game he has proven himself not only a master plotter but an inimitably cool stylist. The best of his thrillers are a pleasure to read, distinguished by crisp, witty prose, (hard-hitting but not so coarse as to be hardboiled), by their effective narrative use of dialogue and, above all, by their sense of absurdity, a kind of cheeky irreverence that has become his trademark.

Unfortunately it is not possible to be cheeky about 20th-century German history. Len Deighton knows this, but he is not comfortable, either, restricting himself to an appropriately serious tone; it turns many of his dialogue scenes into history lessons and gives a flat, textbook quality to whole passages: "But, gradually and grudgingly, he'd come to believe that the new postwar constitution provided a truly democratic framework by means of which Germany would again become the greatest nation in the world . . . The organized violence of the communists and Nazis was a threat to the law, to the stability of German middle-class society, and therefore to everything that Peter held dear." These are unexceptionable sentiments, but even Shirer is more entertaining on the policies of the Weimar Republic.

Still, Winter will be read widely, and probably deserves to be, because the story of Germany's capitulation to Nazi perfidy cannot be told too often: it is never less than appalling, always mesmerizing, always instructive. That Len Deighton's dramatized version is surprisingly pedestrian does not, in the end, detract from the horrible fascination of the story itself. As for Berlin, it will be interesting to see whether, with Winter, Deighton has managed to lay the old city's ghosts, and the scent of its vanished linden-blossoms, finally to rest.

Elizabeth Ward writes frequently about contemporary fiction. Jonathan Yardley is on vacation.