Why would two young men from affluent backgrounds sell classified documents to the Soviets? That's the question at the heart of "The Falcon and the Snowman," but director John Schlesinger treats his characters' motivations like government secrets. Thank heavens these spies come in from the cold -- it's frozen their brains.

Based on the true-life thriller by Robert Lindsey, "The Falcon and the Snowman" relates the stories of Christopher Boyce and Daulton Lee, childhood friends who would grow up to participate in the greatest breach of American security since the Cold War. The film begins when Boyce (Timothy Hutton), suffering a crisis of conscience, drops out of the seminary, so his father (Pat Hingle), a retired FBI man, gets him a job at a defense plant; rapidly promoted, he's assigned to work in the "black vault," monitoring intelligence satellites and, occasionally, stumbling upon errant CIA telexes. His chum Lee (Sean Penn) is a drug dealer specializing in cocaine (hence "snowman"). When Boyce abruptly decides to become a spy trafficking in copies of secret messages, Lee becomes his partner -- for him, the Russians are just junkies with a different habit.

Boyce is known to the Russians by the code name "Falcon," a sobriquet drawn from his interest in falconry; and in the movie, Boyce's pet falcon becomes a symbol of, well, everything. Obviously, he stands for Boyce; but when Schlesinger juxtaposes the falcon in montage with the satellite, which is known in the argot of the black vault as a "bird," he also makes it stand for an America that preys on lesser goverments, an America that Boyce hates. Then it's also intended as a sign of the irreducible innocence of nature (and, by extension, of Boyce), as it whirls above the California countryside in time with Pat Metheny and Lyle Mays' easy-listening jazz score.

The fuzziness of the symbol is fatal to "The Falcon and the Snowman," because it's the best clue we get as to why Boyce enters the espionage racket. The movie opens with a montage of footage of American upheaval, from Woodstock to Patty Hearst to Watergate; Boyce seems traumatized when he discovers that the CIA is working to undermine the left-leaning prime minister of Australia. But if Boyce is stupid enough to think that the Russians are any better, Schlesinger isn't telling -- the movie has no point of view on Boyce's actions, so his speeches of self-justification come in a vacuum.

Boyce's indignation doesn't seem grounded in anything. In his early scenes on the job, Hutton seems bemused by his colleagues' paranoid lunacy; Hingle is so crustily engaging as the father that the confrontation he has with his son, which seems to trigger the treason, doesn't amount to much -- Hutton just seems overwrought. Hutton is an actor of minimal effects, and when he has a role he can sink his teeth into (like the troubled cadet in "Taps"), he can exert a quiet authority. But when, as in "The Falcon and the Snowman," the role just isn't there, his minimalism seems as small and frantic as a gerbil's. Without a story, Hutton simply reverts to his look of eyes-narrowed earnestness -- he seems like a 5-year-old determined to get his tricycle up the hill.

As portrayed in Lindsey's book, the real Boyce was not a victim but a consummate hustler (in the sequel, "Flight of the Falcon," he escapes from prison and becomes a bank robber). Screenwriter Steven Zaillian has adapted the book so that Boyce becomes an innocent, where in the book, what's interesting is his trick of seeming innocent.

The logic, apparently, was to provide a contrast with his hustling friend, Lee -- Penn plays the role for all he's worth. He has the genius to completely re-create himself in each role -- with his new mop-top and nasal cadences that roll like marbles across his tongue, he's completely unrecognizable from the Penn you thought you knew. Demanding "premium prices" from the Russians while he marches around the embassy, jabbing the air with his stubby fingers, he's the consummate huckster -- he might as well be selling used cars. Even his blubbering self-pity is just another sales pitch -- you can see him watching out of the corner of his eye, trying to gauge the effect he's having.

Although he's not particularly short, Penn even evokes the short stature that, in Lindsey's book, was at the heart of the inferiority complex that led Lee to deal drugs -- he walks with hunched shoulders, trying to hike himself up a couple of inches, and he always stands up to talk (that paradoxically ineffective short man's tic).

But since everything that's interesting about Penn's performance comes out of the book, not the script, it just plays like empty bravura. Everything about this movie is backwards -- where Lindsey was fascinated by the way political and cultural themes were engrafted on what was essentially just a scam, Schlesinger starts with an idea of an era, then contends that his characters were the products of it. Instead of a story, there's just a lot of footage of the falcon flying around, toting his subjective camera, and, like the audience, at the end of its tether. The Falcon and the Snowman, opening today at area theaters, is rated R, and contains profanity and some violence.