"Master and Commander: The Far Side of the World"

That particular detail doesn't appear in "Master and Commander," but Weir captures plenty of others; he's done an almost miraculous job of transferring the texture of O'Brian's writing to the screen. Just before the battle that opens the movie, Weir shows us the sailors' rugged hands sweeping their mess table clean. Next we see Stephen's medical implements, a clatter of barbaric-looking knives and cleavers, being spilled onto its surface. When the wounded start coming in, the mess table will become an operating table.

Other details slip into focus without ever being thunderingly obvious: We see how the sailors who die at sea are sewn into their hammocks by their shipmates -- the stitched canvas is like a private cocoon to shelter and protect the dead. We see carpenters working desperately to patch the holes made by the 18-pound cannonballs fired by the enemy ship; water doesn't just pour in around the men -- it shoves them aside, a bullying gush, and still they hammer away. We get a sense of how the crewmen talk to each other, and how they navigate the ship's complex social strata, in which highly experienced sailors from the lower classes need to work closely with upper-class officers who are often young and inexperienced. At the same time, though, it's the officers' duty to fight alongside the men. In the heat of battle, the privileges of class become something of a liability, because if anything, the officers are expected to be braver and nobler than the men under their command.

In one scene, Jack pays a visit to one of his midshipmen, Lord Blakeney, who is no older than 12 or so (and is played with a charmingly old-fashioned demeanor by Max Pirkis, who resembles the young Mark Lester of "Oliver!"). Blakeney has been injured in battle, and so Jack brings him a book about Adm. Lord Nelson, then-commander of the Royal Navy and already a legend. "It has all of his battles in it, and some very fine illustrations," Jack says stiffly, but his voice betrays tremors of awkward kindness. You realize that Jack is speaking to someone who's above his station socially, but who is nonetheless under his authority. And you also see that he's trying to give comfort to a child without patronizing him: He needs to treat Blakeney like a man -- and yet he still recognizes that, for a boy of 12, a book with pictures is far superior to one without.

Crowe plays the scene beautifully -- but then, he's the kind of actor who in his heart would probably like to be Jack Aubrey, a man's man with a fine-grained sense of decency. Bettany's Stephen makes a fine counterweight to Jack. His performance is by necessity more low-key than Crowe's, but it still has weight and heft; even when Crowe's not on screen, Bettany holds the movie capably. Stephen isn't as immediately readable a character as Jack is, and Bettany pulls off the difficult trick of playing a reserved man without holding himself remote from the audience. If Crowe gets some of the biggest dramatic moments in "Master and Commander," Bettany gets some of the most intimate: At one point, after Jack has bitterly disappointed him, Stephen hunches angrily on the deck. Young Blakeney, a budding naturalist himself, approaches him to solemnly proffer a special beetle he's found somewhere on the ship. Stephen accepts the bug and examines it, and Bettany shows us how Stephen is slowly and begrudgingly coming out of himself and back to the more important world at hand, pulled along by the miniature horsepower of a rather plain-looking black beetle.

If Stephen is the man who looks after the details, Jack is the kind of guy who steps on beetles unwittingly instead of pausing to examine them. But he's also the soul of the movie. You need a big actor to stand up to a tall ship, and Crowe steps into the job with ease. Crowe's Jack is a good Navy man, but he'll follow his instincts before he'll follow the rules -- he's something of a rebel, even though he knows the rules exist for a reason. As O'Brian wrote him and as Crowe plays him here, he's a man who makes you understand some of the intricacies of heroism. Jack's heroism isn't just a crazy willingness to, say, run an adversary through with a sword. As Crowe plays him, he makes you understand that bravery is only the half of it, or maybe even less -- the better part of Jack's talent may lie in inspiring so much confidence in his men. At one point he sends one of his young crewmen out on an extremely dangerous mission that requires dropping him into the waters below. He fastens a belt around the boy's waist ("Wouldn't want to lose you!") and then, when the fellow returns, greets him with a clap on the back that, without diminishing the feat he's pulled off, suggests he knew the kid could do it all along: "Now tell me that wasn't fun!"

But Crowe also plays the counterweight of that confidence, because he's not foolish enough to believe he can read the future. He knows men will die as the result of the decisions he makes, and Crowe carries that knowledge on his brow and on his back. Heroes are almost impossible to play, partly because heroism, so affecting in real life, always manages to seem both tinny and overblown by the time it's poured onto a movie screen. But Crowe plays a character and not an ideal. His version of heroism is as much tied in with the way he wraps his mighty paw around one of those teacups as it is with the way he revs his men up as they exercise the ship's guns. Crowe gets some lines that I can't imagine any other actor pulling off. (Examining a model of the state-of-the-art Acheron, he muses, "That's the future! What a fascinating modern age we live in.") But I found myself believing in Jack Aubrey with the same fervor as that kid who got tossed overboard with a puny belt around his waist. Crowe's version of heroism is affable and human, never hokey or forced. Instead it feels modern and solid, like a smooth, hefty chunk of silver.

Weir has the right visual sense to go with that kind of heroism. There are times when Boyd's work is the cinematic counterpart of a Turner painting; he seizes the essence of nature's turmoil and renders it with devastating softness. Unlike so many other contemporary action pictures, which translate all too willingly and reasonably to the small screen at home, "Master and Commander" is stubbornly cinematic. Boyd gives us a close shot of Jack and his second-in-command, Tom Pullings (James D'Arcy), laughing in the wind, and then pulls back, way back, to show us that they've climbed to the top of the tallest mast.

It's a long shot that shows us how tiny and inconsequential the men are in the context of the sea around them. But in the context of the movie itself, they and their ship are everything. The two men look small, holding fast to the rigging around that mast. But they're still bigger than life, resolutely holding their place in a very big picture. Because, above all, "Master and Commander" is a picture with a human sense of scale. There are already plenty of conflicts in literature, as well as in life: Man vs. man, man vs. nature, man vs. himself. Man's got enough problems. He shouldn't have to be battling the movies too.

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