Especially given recent events in Boston, it’s a salutary project to try to understand how Muslim immigrants who have lived in the US for a considerable time can be radicalized. And though there’s no act of terrorism in “The Reluctant Fundamentalist”—at least not of the Boston variety—that’s what Mira Nair’s adaptation of Mohsin Hamid’s novel is about. It’s an earnest, serious film, but ultimately one that fails to satisfactorily dramatize the subject—or to transcend a bare, frustrating didacticism in the telling.

To be sure, there is an attempt to give the story the air of a suspense thriller by presenting it in the form of a tense conversation between the title character, Changez Khan (Riz Ahmed)—now a university teacher in Pakistan suspected of radical dealings—and American journalist Bobby Lincoln (Live Schreiber) in a coffeehouse filled with Khan’s volatile students, all the while being watched by US intelligence agents headed by Martin Donovan. (The background to the interview is the kidnapping of one of Khan’s colleagues, a westerner who was snatched off the streets and is now a hostage threatened with death.)

But this set-up really doesn’t create much real suspense, despite divulging secrets along the way (about Lincoln as well as Khan), partially because the revelations aren’t terribly surprising, but also because the explanations presented for Khan’s turn from westernized yuppie to committed traditionalist (and nationalist) are banal, and carry an unfortunately hagiographic tone, turning him into a long-suffering, saintly figure. And though one senses that Nair is grappling for a more complex portrait, her efforts end up opaque and fragmented, never taking hold.

So what is it that changes Khan, who emigrated to the US to go to an Ivy League school and then, once graduated, took a job with a Wall Street firm that specializes—like Bain Capital—in analyzing businesses to make recommendations about strengthening their bottom lines. Swiftly ascending the ranks under the guidance of his oily, shrewd mentor (Kiefer Sutherland), Khan also profited by linking up with Erica (Kate Hudson), the photographer daughter of the firm’s CEO, whom he meets in one of those cute, serendipitous encounters (in Central Park, no less) that would really be more at home in a romantic comedy than here. Khan’s success in the materialistic New York financial world is the fulfillment of his dream, even though back home his poet father (Om Puri) has serious reservations about the path his son has chosen.

But Khan’s path is irreparably altered by 9/11, which initiates a stream of indignities, ranging from intrusive searches at airports and profiling by local police and federal agents to suspicious glances from colleagues at the office and even what he perceives as a betrayal by Erica, who uses his experience as inspiration for her latest photo exhibit. (The only co-worker who remains friendly, in one of the script’s most heavy-handed moves, is a genial African-American, played by Nelsan Ellis—another societal outsider in the privileged white world, you see.) His reaction leads him to go back to his Pakistani roots and finally to reject his westernized persona—and his cushy job—when his firm sends him to Istanbul to assess the viability of a publishing firm specializing in Middle Eastern culture and ordering it closed. Rather than falling in with that decision, he quits and returns to Pakistan to become a teacher and (the CIA estimates) a dangerous rabble-rouser.

But has his embrace of his Pakistani pride actually led him to the promotion of—and even participation in—violence? And is the American desire to retrieve the hostage professor really a matter of altruism? Those are the questions that “The Reluctant Fundamentalism” tries to address. But by doling out clues through Khan’s monologue-cum-flashbacks, the process becomes more than a little didactic—and frustrating. Khan chooses to tell his story in a way designed to keep many things hidden until the screenplay can spring them for maximum impact, and the result is at once simplistic and opaque. You understand why the picture is constructed as it is, but the effect is to make one both impatient as the narrative progresses and unsatisfied when the conclusion finally arrives. It’s also curious that apart from one scene in Turkey, the religious dimension is given very short shrift.

Still, the film has virtues. Nair and cinematographer Declan Quinn make good use of the Pakistani locales, achieving a real sense of place and atmosphere (the astute use of music by Michael Andrews is a definite asset in this regard, too). Ahmed cuts an attractive figure as Khan, though the character’s reserve doesn’t allow him to shine, and Sutherland certainly carries an aura of quiet menace. Less impressive are Schreiber and Hudson, though both get by, while Donovan is simply wasted in a stock part. On the other hand it’s always good to see the authoritative Puri, even when as here he’s not given enough to do, and Haluk Bilginer makes a strong impression as the Turkish publisher as well.

One has to respect Nair for her ambition. But though one can admire the film, that’s balanced by regret for its flaws.