Rated R. 128 minutes. At the Esquire Theatre.

It's no wonder that the words "Islamic" and "fundamentalism" are often so tightly coupled in American minds: Even our dictionaries bind them together. On the Merriam-Webster website, for instance, fundamentalism is partly defined as "a movement or attitude stressing strict and literal adherence to a set of basic principles <Islamic fundamentalism>."

In his slim 2007 novel, "The Reluctant Fundamentalist," the Pakistan-born writer Mohsin Hamid takes these two words and rubs them together until they throw off intellectual sparks. Written as a monologue, it is a somewhat claustrophobic blurt of a book that, given world events, continues to feel eerily timely.

The monologue is delivered by Changez — a young Pakistani university lecturer grievously, possibly violently disenchanted with the United States — to an unnamed American who may be some kind of U.S. operative. Seated in a Lahore restaurant, Changez essentially keeps the mystery man (and the reader) captive with his reminiscences of his American dreams and disappointments both in work and with a wealthy melancholic woman who, rather like her country, let him down.

Comparing books to the movies made of them isn't always necessary or productive, but it's instructive when the results are as thuddingly crude as Mira Nair's take on "The Reluctant Fundamentalist." Blunt where the novel is subtle, it follows its source in outline, with Changez (a fine Riz Ahmed) narrating his tale to the stranger, here a journalist with a preposterous name, Bobby Lincoln (Liev Schreiber), and a fairly clear-cut relationship with the U.S. government: He's seeking information about a kidnapped American. Now, when the men sit down together they are in the gunsights of a CIA team led by an operative, Ludlow Cooper (Martin Donovan), who's keeping up a second conversation with Lincoln through an earpiece and cellphone calls.

The agents, their guns, the sweat pouring off them, the urgency of their voices and gestures — an urgency mirrored by the restless camerawork, brusque edits and percussive music — give these scenes the flavor of a thriller. They have no parallel in the book, in which a glint of metal from inside a man's jacket telegraphs potential violence to come.

Nair's decision to pump up Hamid's story with genre elements partly registers as a pragmatic commercial decision, as a way to package and sell ideas about U.S. power and subaltern identities. And there's no question that the images and sounds of guns being cocked, as well as black SUVs hurtling heavily armed U.S. agents through dusty Pakistani streets, add evocative jolts to the movie and its advertising.

Yet by literalizing the idea of U.S. military aggression and all that it implies, Nair doesn't just invest Hamid's story with Hollywood-style beats, she also completely drains it of ambiguity.

As in the novel, the movie follows Changez after he graduates from Princeton, finds success working for a company that estimates the value of other firms (and shuts down the failing ones) and falls in love with Erica (a miscast Kate Hudson).

After Sept. 11, though, he begins to see himself a stranger in a strange land, and alienated from America and its conquering (call it fundamentalist) capitalism. "In this constant striving to realize a financial future," he says in the book, "no thought was given to the critical personal and political issues that affect one's emotional present."

More provocatively, in a pivotal scene midway through the novel, Changez (Genghis in Urdu) also says that he smiled when he watched images of the Twin Towers collapsing on Sept. 11. "Yes, despicable as it may sound, my initial reaction was to be remarkably pleased." He was, Changez continues, caught up in "the symbolism of it all, the fact that someone had so visibly brought America to her knees." The shock of that smile and its meaning — is this the admission of an ordinary, aggrieved man or a terrorist? — reverberates through the remainder of the book.

He's a narrative conceit in a novel that puts different fundamentalisms into dialectical play.