IN A Mighty Heart—a 1912 film title if ever there was one—Angelina Jolie plays Mrs. Daniel Pearl, the wife of the former local man and martyred Wall Street Journal reporter. In January 2002, Pearl was investigating the links between Pakistani jihadists and the "shoe bomber" Richard Reid, whose name we all routinely curse when trapped at the security gate at the airport. (For Reid, I wish neither torture nor capital punishment—just agonizing waves of doubt and pangs of agnosticism at 3am.)

Stolen away by the people he had tried to interview, Pearl (Dan Futterman) was kept prisoner and eventually horribly murdered. Meanwhile, Mariane Pearl, five months pregnant, waited for news. Mariane's memoir is unmuddied by calls for vengeance or by sobbing writing, and Michael Winterbottom's cryptodocumentary approach tries to preserve something of her nobility. Winterbottom's method resembles what he did in his previous film, The Road to Guantanamo. In a summer of sequels, A Mighty Heart can be counted as just one more.

According to his kidnappers, Pearl's murder was payback for the terrible conditions at the Cuban military base. Freeing the jihad POWs was one of the demands made by the fanatics who filmed Pearl's execution and uploaded it onto the Internet. Winterbottom mentions this demand, while showing the brutal methods the Pakistani police used in tracking down and torturing suspects.

Anxious not to take sides, Winterbottom still portrays the Americans as conspirators and loiterers—and, in the case, of the embassyman Randall Bennett, possessors of a sadistically vengeful streak. (Bennett is played by Will Patton, the go-to actor for portraying government weasels.)

If we see these Yanks hanging out at the lobby bar of the Sheraton, they deserved their drinks; the green zone in Karachi is apparently a tremendously hazardous place. I got that info from William Dalrymple's essay in The New York Review of Books on the book A Mighty Heart: The Brave Life and Death of My Husband, Danny Pearl and Bernard-Henri Lévy's meretricious, Paki-bashing bestseller Who Killed Daniel Pearl?. Dalrymple's piece was about a thousand times more enlightening than this film.

When I was in college, I heard Karachi described by a former citizen as the dirtiest city in the world; I doubt if it's cleaner today. Winterbottom scans a little of the dirt and the danger, but he has a darting, home-movieish lens and less sense of where or when to cut than most practitioners of hit-and-run filmmaking. At great hazard to himself and his crew, Winterbottom filmed locations in that Pakistani megalopolis before heading for Mumbai to finish the film. He delivers chaotic and hardly informative images: a traffic jam that never ends, a supermarket, carrion-eating birds flapping and croaking, the domes of mosques against a smoggy sunset. Hordes of goats materialize as the film reaches its climax; there are as many goat-reaction shots in A Mighty Heart as in a Dr. Doolittle movie.

At least the local color gives us a break from watching Angelina stew in her juices. We never join Daniel Pearl in his ordeal. Would it have been encouraging the enemy to look in upon the kidnapper, Omar Sheikh, another apparently civilized Westerner who made his choice for medievalism? The police investigation is slightly more dramatic than the scenes of Mariane Pearl watching, waiting, holding uncomfortable dinner parties and talking into a cell phone and waiting for news.

If Pearl was apolitical, so must we be; Winterbottom gives us no way to understand the fanatics. Nor is their any suggestion of what Pearl felt, representing the Wall Street Journal as a balanced reporter. In those days, the WSJ's editorial writers outhawked the most bloodthirsty D.C. wonks.

But in this tepid and monotonous film, one observes the world-famous diva and waits for the high note. Jolie's big scene comes when Mariane views the fateful VHS tape (we're spared it) of her husband's murder and wails to the heavens. The shriek is supposed to be such a crowd pleaser that Jolie reprises it during a later childbirth scene.

Jolie understands that she is the one with the mighty heart, even though Mrs. Pearl was referring to her late husband. What used to make Jolie unique onscreen was her dangerousness. She once had a love affair with edged weapons—is she at her best cast as someone who sits around while someone else gets ready to use a knife? Here, Jolie tests her new accent—Franco-Cuban—and her new look. She's coated with skin bronzer. Drastic curls dangle on her forehead, making her look as weirdly exotic as the ladies in encaustic funerary portraits of ancient Egyptians. Maybe with a nonstar in the role, Winterbottom would have had a better chance of getting the sense of an ordinary person caught in an inconceivable situation.

But who knows who could save A Mighty Heart? Winterbottom's reach exceeds his grasp with regularity. This is the kind of film that gets called great, because it has a great subject; those who recommend it realize that few will actually steel themselves to go see it, and far fewer will get back to you to tell you how dull it was.

A Mighty Heart (R; 100 min.), directed by Michael Winterbottom, written by John Orloff, photographed by Marcel Zyskind and starring Angelina Jolie, opens June 22 at selected theaters.

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