The blend of story and character - how well or how badly each is conceived and both are combined - usually dictates a novel's literary success. Working out the symbiosis between a tale and the people who inhabit it and make it come alive can be done in countless ways. The best of George V. Higgins' thrillers - most notably "The Friends of Eddie Coyle" - are told largely in dialogue; the characters make the plot by virtue of who and what they are. Frederick Forsyth's books are huge commercial successes but they don't work as novels very well. The stories are superb; the people are pasteboard.

Robert Littell's new novel, "The Debriefing," takes the standard elements of the modern spy story - supersecret U.S. military intelligence group reporting directly to the chairman of the Joint Chiefs of Staff, and its shadowy opposite in the Soviet Union: street, bedroom and restaurant scenes in Washington, Moscow and Paris - and turns them into a novel of great enchantment because of the people who move through the settings and imperatives.

The hero is Stone - he has no first name - who isn't getting any younger, whose supremacy within the supersecret intelligence group is threatened by Mozart, a different, passionless and bureaucratic sort of spy. Stone, the son of Jewish immigrants from the Soviet Union, has his passions; he knows that some of them will wither with time and that others - his estranged child, his country, his ideas - will always be with him.

Oleg Kulakov, a Soviet diplomatic courier whose defection in Athens triggers the plot of "The Debriefing," is a superb portrait of a man whose life has been ruined by experts in the life-ruining business.

To double, triple and quadruple check on the possibility that Kulakov is a planted defector, Stone has the help of the small staff of Topology - code name for the super-secret group of experts on the U.S.S.R. - and Thro, a member of the group and Stone's mistress in a relationship he knows is doomed. Thro is beautifully drawn, sexually and verbally, with an apocalyptic sense of humor.

The ultimate check on Kulakov requires someone to go to the Soviet Union - unsanctioned by the U.S. government - and go back over all the people in the life story he has related. The multilingual Stone chooses himself.

Robert Littell obviously knows the Soviet Union, or can vividly imagine its physical decay, lingering splendors and ethnic multiplicity as Stone moves from Moscow to Leningrad to Alma-Ata.

But this is a novel of people, and the Russians with whom Stone makes connection ultimately wipe out the extreme tension Littell could have wrung from his basic plot: Yekaterina Katushka, a 25-year-old quasi-mystic and eccentric who works as a hooker, defies the Soviet system by raising plants in an illegal, jerry-made greenhouse on her apartment house roof and reads Akhmatova's poetry; Katushka's apartment mates; a man who was Stalin's double and his transvestite lover; a broken but spiritually defiant Jewish janitor; spies; soldiers; bureaucrats; an aging nymphomaniac.

With some of them Stone makes connections dictated by plot; with others he makes human connection. Through him, we come to love Katushka, and the heart leaps toward Morning Stalin, whose life had meaning only through his resemblance to the Soviet tyrant - until Stone appeared. The whiff of Russia is in these people; they embody the Slavic mixture of irony and whimsy. "Here we never weep at sadness, only happiness," one character says. "That way we cry less."

I wish Littell had gotten Stone to the Soviet Union earlier - the novel is more than half over before its engrossing center gets under way - and that Stone could have stayed there longer.

From the surfaces of "The Debriefing" we learn all over again about those symmetric absurdities of East-West conflict that are probably true: Soviet military intelligence hates the KGB as much as U.S. military intelligence has contempt for the CIA; ultimate alliances are made between specialists and visionaries, not political or ideological soulmates. The cold war is long over; its practices, reactions and cruel bureaucracies continue not because the U.S.S.R. and the United States are terrified of each other as much as because each is afraid of itself.

None of that matters as much as Robert Littell's characters. They will stay with you for a long time, long after this first-rate summer read is put away for a winter of Big Books and the usual discontents.