Grade: C

An argument could be made that Edward Zwick has become our contemporary Stanley Kramer. The latter was a mediocre filmmaker who, during the fifties and sixties, gave his pictures prestige by addressing pressing social issues in an earnest if cinematically flatfooted way. Zwick may be working some decades later, but he’s following much the same blueprint. Whether it’s racism (“Glory”) or female equality (“Courage Under Fire”) or personal freedom versus social order (“The Siege”) or the clash between tradition and modernization (“The Last Samurai”), Zwick has planted the issue in a dramatic context–often involving the military–that allows for some crowd-pleasing action to coat the didactic pill, as it were, in the trappings of popular entertainment. It’s a ploy that’s worked for him as it did for Kramer–his movies have been taken more seriously than they actually deserve to be. And though he’s a more adept director than Kramer was (even his best pictures, like “Inherit the Wind,” weren’t much beyond mediocre, while most, like “Guess Who’s Coming to Dinner,” are simply inept), Zwick’s work is still more than a little pedestrian and anonymous.

He follows the familiar pattern with “Blood Diamond,” which takes a matter of contemporary concern–the exploitation of Africa by western powers, and the devastation it causes–and presents it in the form of an action-adventure featuring a colorful though troubled white rogue, the simple but honorable local fisherman who becomes his possible ticket to wealth, and the beautiful, principled journalist who’s drawn to the adventurer despite his checkered past and emotionally devastated by the plight of the fisherman and his land, devastated by war. If you pierce through the self-importance, you just might spy a dose of “The African Queen” mixed with a dollop of “The Defiant Ones” here, though the effect is more like the latter–a Kramer movie!–than the former.

In the picture, set in 1999 Sierra Leone, Leonardo DiCaprio plays Danny Archer, a battle-tested young man, born in what was then Rhodesia, who’d once fought in the ranks of South African Colonel Coetzee (Arnold Vosloo), now head, it seems, of a private army of soldiers of fortune. Archer is in the employ of a British diamond firm, smuggling gems mined by laborers enslaved to a brutal anti-government guerrilla army into a neighboring country. He’s caught and briefly jailed by soldiers, but while incarcerated he learns of a large stone secreted away in the wild by another inmate, Solomon Vandy (Djimon Hounsou), a villager who’d been seized by the guerrillas to serve as a worker, while his beloved young son was taken by them to be brainwashed into one of their “child soldiers” controlled by drugs and inured to violence. Wanting the diamond to get out of Africa, Archer promises the reunite Vandy with his family if he’ll lead him to it. And to finagle their way past sentry posts into the war zone where it’s buried, Danny uses his charms on the implausibly squeaky-clean, highly principled American reporter Maddy Bowen (Jennifer Connelly).

It wouldn’t be of much import to track the ins and outs of what follows. Suffice it to say that along the way Archer’s venality gradually turns to something more redemptive and (as the autobiographical details he pours out to Maddy in a breakthrough moment suggest) he will eventually prove a self-sacrificing fellow, willing to give up much to help Maddy uncover the nefarious schemes of the diamond firms making a killing off the continent’s blood-soaked gems. And, of course, the gruffness he originally shows toward Vandy is transformed into unexpected brotherhood, so much so that he’ll abandon his own dreams–and more–to reunite the man with his family.

This is very formulaic stuff, made even worse by a decision to add so many climaxes to the last half-hour that by the time the final one comes along, it feels like an exhausted runner completing the ultimate lap in a marathon. And although the picture has the courage–if that’s the right word–to choose the less crowd-pleasing of the two obvious conclusions to its romantic plot thread, one can give it credit only for electing the lesser of two banalities. There’s also something vaguely unseemly about using the civil war of the nineties in Sierra Leone as the film’s backdrop, especially in terms of the subplot involving Vandy’s son and his initiation into the company of child soldiers. That phenomenon is a horrifying business, certainly worthy of serious screen treatment; but here it becomes little more than a mechanism for a soapoperatic episode.

As for the cast, it’s pretty much DiCaprio’s show. Strutting about with an air that combines wounded experience with boyish charm, and sporting an accent that goes on and off, he easily dominates his co-stars. Except for a few moments when he’s allowed to show his emotions at full throttle, Hounsou is restrained and dignified in the same way Brock Peters was in “To Kill a Mockingbird” half a century ago, and Connelly is even less challenged than she was in the recent “Little Children.” Despite its epic length, this is basically a three-character piece, in which apart from Vosloo no one else makes much of an impression. Technically all is well, with ace cinematographer Eduardo Sierra capturing the African locations skillfully in widescreen format, though James Newton Howard’s score is nondescript.

The issues raised by “Blood Diamond” are real. But as with most of Zwick’s films, the high principles and good intentions don’t compensate for the obvious point-making and flabby execution. This film joins “The Interpreter” and “The Constant Gardener” as another attempt to convey the torment of post-colonial Africa that doesn’t fulfill its ambitions. “The Last King of Scotland” comes closer to the mark.