Akira Kurosawa's The Seven Samurai (1954) stands unchallenged as celluloid's defining elegy for Japan's heroic warrior class, which is shown nobly dying off, already redundant, during the civil wars of the 16th century. But some samurai stuck it out for centuries afterward - as we see from Nagisa Oshima's fascinating, tantalizing revisionist Taboo (at the Brattle Theatre June 15 through 21), where in 1865 the Shinsengumi clan is still extant.

These Kyoto-based warriors (this part is actual history) had distinguished themselves a year earlier at the battle of Ikeyada. Now the downslide is starting, though they keep up the iconic appearance of samurai at the top of their game, wearing their spiffy robes and sitting cross-legged on their mats while stoically observing the potential recruits who audition to join their mighty company.

More and more, however, the Shinsengumi are forced to pick from the lower classes, sons of traders and even out-and-out peasants. Character has been ruled out as a factor in choosing initiates. Instead, everything comes down to prowess at swordplay - which is why, against their better judgment, the Shinsengumi leaders invite two unlikely young men to join their clan: Hyozo Tashiro (Tadanobu Asano), an excitable low-caste type, and Sozaburo Kano (Ryuhei Matsuda), who with his Modigliani almond eyes, rose-petal lips, ponytail, and bare feet looks less a combatant than a bedeviling young woman.

Nagisa Oshima, left-wing and impolitic, was the first director ever to show sexual penetration in an art movie, in the groundbreaking 1976 In the Realm of the Senses. This time, he explains, he's out to challenge the traditional sexual ethos of samurai movies. " In the past, no one dared touch the subject of homosexuality, whether it was latent or overt. In my opinion, one cannot understand the world of samurai without showing the fundamental homosexual aspect. "

Kurosawa, a macho macho moviemaker, might be groaning in his grave at how, in Taboo, Oshima toys with and turns upside down the he-man concept of samurai. The lovely-locked Sozaburo wreaks havoc on the Shinsengumi clan, who are, with a few exceptions, a bunch of Kyoto closet queens! Those guys who don't blurt out to Sozaburo their desire to sleep with him (a samurai in heat: " I'd give my life to wake up to the nightingale's song after holding you in my arms all night " ) at least, as the discreet English subtitle explains, " lean that way. " Everyone accuses the others of being secretly smitten. Sozaburo gets off on all the attention, becoming quickly the lover of Hyozo but also the secret squeeze of several others in uniform, as they make the beast of a back (theirs) and a bottom (his). " Why did you join? " he's asked; he smiles coyly while Oshima answers by cutting to the barracks at night, a hundred semi-undressed male bodies.

No question that Sozaburo distracts the horny men from their samurai duties. But there's far more to worry about from this epicene, minx-like young man. Beneath his flirtatious lashes are the coldest eyes; and it seems eerie and inhuman to even the most hardened veteran how easily he carries out an order to execute an errant samurai. He slashes off the head, then holds it matter-of-factly before his commander, like a cat showing off in its jaws a broken-necked mouse.

Samurai noir? The one-second death by sword of a surprised character replicates (intentionally? coincidentally?) the blink-and-you'll-miss-it gunning down of Sam Spade's partner Archer in The Maltese Falcon. Noir is the genre that the piano music of Ryuichi Sakamoto evokes, especially the paranoid motif that plays over Sozaburo in close-up. He's a fem " femme fatale " ; the second time he's asked why he joined the samurai tribe, he replies, " To have the right to kill. "

Taboo evolves into a murder mystery as dead bodies, sliced by swords, pile up. There's even a kind of amateur detective on duty, Toshizo Hijikata (cult actor/filmmaker Takeshi " Beat " Kitano), contemplative captain of the Shinsengumi. He is the first to surmise that Sozaburo and Hyozo are lovers, from the odd way they swordfight together. But by the time he really figures out Sozaburo, it's too late. He spits and impotently cuts down a cherry tree. Oshima: " For me, this gesture symbolizes the destiny of the samurai - in other words, their end. "

Gerald Peary can be reached at gpeary@world.std.com.

Issue Date: June 14-21, 2001