In theory an old-fashioned international thriller, produced with the slickness and political savvy the Hollywood studios once regularly brought to such projects, should be welcomed with open arms in this age of empty-headed, explosion-laden adventure flicks. That’s why “The Interpreter,” a convoluted suspenser with a United Nations setting, starring top-flight performers like Nicole Kidman and Sean Penn and directed by the man who gave us one of the classiest examples of the genre, “The Three Days of the Condor,” starts out with a distinct advantage. Unfortunately, the reality doesn’t fulfill the promise. Sydney Pollack’s attempt to replicate the success of his 1975 picture proves about as disappointing as the remake of the “The Manchurian Candidate” was last year. Like that Jonathan Demme film, it stumbles in both content and execution, even though it’s certainly more high-minded and smoothly made than the usual run of contemporary action fare.

Kidman has what amounts to the Robert Redford role as Silvia Broome, a U.N. translator originally from a fictitious south African country called Matobo, ruled by Dr. Suwanie (Earl Cameron), an erstwhile freedom fighter who has become, in his old age, a brutal ethnic cleanser referred to as The Teacher. (Just think of him as a combination of Robert Mugabe, Slobodan Milosevic and Papa Doc Duvalier.) Broome, a cooly efficient type but with a clearly troubled background, goes back to her booth overlooking the General Assembly late one night to retrieve some personal items and chances to overhear, through a microphone unaccountably left on somewhere on the floor, a disembodied voice whispering about a plot against the life of The Teacher, who’s scheduled to address the assembly shortly in an effort to forestall international action against his regime. At once a team of Secret Service agents–morose, cynical Tobin Keller (Sean Penn) and wise-cracking Dot Woods (Catherine Keener)–is dispatched to question Broome, and they’re quickly joined by wily Matoban security chief Nils Lud (Jesper Christensen). The consensus, especially after revelations about Silvia’s past political activities at home, is that she may have been imagining things, but after she’s threatened at her apartment, Keller changes his mind and becomes her protector. What follows is a convoluted procedural involving two of Suwanie’s rivals–one of whom, a smooth-talking exponent of the capitalist line named Kuman-Kuman (George Harris) lives in exile in NYC–as well as Silvia’s activist brother Simon (Hugo Speer) and a mysterious photographer named Philippe (Yvan Attal), who–as we see in a prologue–witnessed the killing of two men back in Matobo, as well as several suspicious staffers at the U.N. itself. And it closes with a would-be nail-biter of an ending reminiscent not only of “Candidate” but Hitchcock’s “The Man Who Knew Too Much.”

Pollack’s film is certainly professionally mounted–Darius Kjondji’s cinematography is expert, and though James Newton Howard’s score can get overly bombastic, the production design (Jon Hutman) and art direction (Tom Warren and W. Steven Graham) are top-notch. The acting is solid, too. Kidman combines steeliness and vulnerability as the linguist, and Penn caps his usual volcanic personality effectively to portray a man beaten down by circumstances. The supporting cast is also strong, with Cameron and Harris offering especially incisive cameos. And “The Interpreter” does feature some well-wrought set-pieces, most notably a really exciting sequence involving a city bus, which is easily the picture’s high point. But there are serious drawbacks as well, especially in the areas of coherence and pacing. The rationale that’s eventually revealed for Keller’s moodiness strains credulity–it’s hardly likely that an agent would be put back in the field so quickly after a tragedy such as he suffered–and Silvia’s attitude remains somewhat opaque even at the close. The finale is capped off with a twist that doesn’t seem believable, and though it’s nice to encounter a picture that resists the natural inclination to throw the leads together in a romantic clinch in the end, the last scene here has a tentative feel that isn’t entirely satisfying (not helped in this case by Penn’s unusual reticence). But the most crippling flaws in the film are that, in the first place, what’s at stake–while morally significant–doesn’t have the world-shaking resonance such matters ordinarily possess in thrillers like this, and second, that the event that sets the plot rolling–Silvia’s overhearing that threatening conversation–not only requires one to accept a bewildering set of coincidences but, in the final analysis, doesn’t easily compute with the revelations at the close. And since Pollack helms the picture in so stately and sedate a fashion, it can’t entirely overcome the problems; quite simply, there’s too much opportunity for you to meditate on the plot weaknesses, and for your interest to flag, as the narrative unfolds. The same difficulty of excessive length beset Hitchcock’s “North by Northwest”–which also involved the U.N. in some international skullduggery–but there the lightheartedness of the project and Cary Grant’s easy charm made the journey a pleasant one; here Pollack’s dour, rather pedestrian approach leaves too much of his film pretty heavy going.

“The Interpreter” represents the first time that permission’s been given for actual filming in the U.N. building, and Pollack and his crew make good use of the opportunity. The General Assembly and Security Council, as well as various public areas, give the picture a sense of surface authenticity that’s quite impressive, especially as they’ve been captured in Khondji’s elegant cinematography. It’s a pity that by contrast the action set in the locales proves less compelling.