Chris Cooper brings a reptilian charisma to Hanssen, who on the surface seems your normal, uptight 25-year FBI man. He’s a right-winger, a fanatical Catholic, bitter about his thwarted ambitions, and a real grump to work with. He also likes kinky sex on the sly, devout rosary-reciting wife Bonnie (Kathleen Quinlan) notwithstanding, or so FBI special agent Kate Burroughs (Laura Linney looking as if the last time she’d got laid was before the Wall came down) tells trainee Eric O’Neill (Ryan Phillippe), whom she assigns to catch Hanssen surfing naughty Web sites.

If only it were that innocent. Hanssen would prove the biggest turncoat in US spy history, selling out his country for 22 years before anyone grew suspicious. The unlikely O’Neill serves as the FBI’s unlikely point man in the investigation, his connection with the creepy but oddly appealing enigma developing from browbeaten gofer to son surrogate, fellow churchgoer, and near-confidant. The relationship plays havoc with O’Neill’s marriage, especially when Hanssen drops by with the wife to cook dinner and investigate his own suspicions about O’Neill. More important, O’Neill’s grudging affection and sympathy for Hanssen tears at his dedication to duty — and his career ambition.

Action-wise, that’s about as rowdy as Breach gets. As in his previous film, Shattered Glass (2003), Ray sets most of the drama in nondescript offices where he subtly stirs the tension of double identities, twisted duplicity, loyalty, honor, and betrayal. Unlike that movie, though, Breach focuses on those tracking down the deceiver rather than on the mystery man himself. Phillippe makes for a colorless hero (though the equally callow Hayden Christensen made for a beguiling villain as plagiarist Stephen Glass), and after a good start (Cooper seems invulnerable and omniscient in his prickly orneriness), Hanssen just rolls over.

Why not tell the whole story from the point of view of someone who could, as did Hanssen at one point, icily oversee the task force investigating his own security breach (“He’s smarter than all of us,” Burroughs confesses to O’Neill), someone who by his own admission got a rush knowing he was the only person in the room who knew he was the one everyone was hunting for? Instead, in a cornered, Iago-like moment, Hanssen speculates on what his motive was — not the money, he says, not the ideology — but then breaks off and says the reason why makes no difference. As those spy thrillers from the ’60s demonstrate, it makes all the difference in the world.