There are a lot of reasons to be enthralled by Blood Diamond, Edward Zwick’s new action-drama-with-a-conscience: the deeply disturbing story he tells, for one, about how American consumer demand for diamonds and European colonialism drive and support horrifying civil strife in impoverished Africa is one that comparatively few people are aware of, and will be appalled to learn. I’d like to think that Jennifer Connelly’s (Dark Water, House of Sand and Fog) activist American journalist character is right here: I’d like to think that if more American brides knew that someone had to lose a hand, or a child, or a home, or a village, or a life so they could have the diamonds for their fairy-tale weddings, far fewer American brides would want those diamonds. It remains to be seen whether even a movie this powerful can change enough minds -- this one certainly is unsettling enough that it might have a chance. The sequences of the indoctrination of children, the sickening brainwashing they are put through in order to turn them into soldiers-- nay, killing machines for sadistic rebel militias that pay for their weapons with diamonds mined by slaves and smuggled out of conflicts zones are positively haunting.

The plot of Blood Diamond -- revolving around an escaped slave miner (a passionate Djimon Hounsou: The Island, Beauty Shop) who has hidden from his masters a ridiculously valuable pink diamond he discovered, meaning to use it to pay to recover his disappeared family -- is fictional. But its setting, 1990s Sierra Leone, is real, and Zwick (The Last Samurai, The Siege) and cinematographer Eduardo Serra -- who also shot the luminous Girl with a Pearl Earring, among other beautiful-looking films -- put it on the screen in a gorgeously gritty way, the dramatic landscapes of Africa looking both lush and ravaged, so that we understand why people have fought over these places and see the result of that fighting at the same time. This is one of the more beautiful ugly films I’ve ever seen -- one visual juxtaposition in particular sticks with me, of a party at a bar on a pier at the edge of a city while the flashes of explosions, the herald of approaching rebel militias, light up the sky in the distance, the partyers all but oblivious. And Zwick isn’t afraid to use the tropes of straight-up action movies -- car chases, gun battles -- to tell a story with far more consequence than the typical shoot-‘em-up: this is a hugely electrifying film in many places, but in a downbeat way. When you’re breathless at the end of an intense sequence, it’s with a relief you share with the characters, and not from a let’s-do-it-again roller-coaster thrill. You’re glad it’s over.

But probably the most stunning aspect of the film is Leonardo DiCaprio’s performance as Archer, African himself -- he’s from Zimbabwe -- yet deeply complicit in maintaining a status quo that is good for him, great for his employers, and unspeakably dire for most of the people of Africa. Archer is the brutal centerpiece of a brutal film, and DiCaprio (The Aviator, Catch Me If You Can) is riveting and utterly, awfully convincing -- teamed up with Hounsou’s diamond miner slash grief-stricken husband and father to find the diamond, of which he learns only accidentally, Archer is all hard case, unmotivated by anything but self-interest. The script, by Charles Leavitt and C. Gaby Mitchell, is smart, smart, smart -- it doesn’t overanalyze or overexplain Archer and his motivations, just gives you enough to appreciate why he does certain things that might seem like sentimental claptrap or mere plot necessity in a less smart movie. (Archer sneers Connelly’s journalist at one point, “You Americans, you’re always talking about your feelings” -- Leavitt and Mitchell spare Archer, and us, such indignities.)

Much of the credit for Archer’s force and integrity as a character -- even if as a man, his integrity is questionable -- is down to Dicaprio: this is his arrival as a genuinely grownup actor, even more so than his powerful performance in The Departed, earlier this year. Just when the film gets us to the point where you fear that Archer is softening a bit, going Hollywood mushy, wham! he’s suddenly even more coldly efficient than he had been. And you believe DiCaprio: he doesn’t look like an actor having a lark playing a bad guy. He looks and sounds and feels like the real deal.

(Technorati tags: Blood Diamond, Leonardo Dicaprio, Edward Zwick)