David Henry Hwang's brilliant 1988 play M. Butterfly hangs on gender ambiguity, so it's bound to seem different now than it did then, since gender ambiguity is not what it was thirty years ago. The M. in the play's title, denoting Monsieur Butterfly, preserves the confusion on which the show's plot and politics rest. But the big reveal, so shocking in the original production, is no longer a surprise, since everyone now knows what the title told us all along, that she is a he.

Not only have sexual politics changed since the 1980s, but global politics have as well. Hwang's underlying assumption, fundamental to the U.S. involvement in Southeast Asia, was that the dominant masculinized Western will easily prevail over the submissive feminized Asian, with all the arrogance and sexual entitlement, the "international rape mentality," that implies.

The play's political context is the French and American wars in Vietnam, so when a love affair between a French diplomat and a Chinese opera star in Peking begins, it turns on the complexities of espionage.  The role of China in the world has shifted considerably since Mao, so M. Butterfly, always a history play, has become more distant in time, more remote in attitudes.

The many dichotomies Hwang builds into the drama — not just East/West, but also the ancient East/the new East, communism/capitalism — are further complicated by the psychological dichotomies of fantasy/reality and mind/body. Further, because the plot pivot is Puccini's opera Madame Butterfly and the Pinkerton syndrome, there is the additional dichotomy of Japan/China — no longer so easily confused in the Western mind — with the clashing musical dichotomy of European opera and traditional Peking opera. With all this, the male/female binary suddenly seems simplistic.

Based on a bizarre-but-true story of a French diplomat, here called Rene Gallimard (Clive Owen). For 20 years he was the lover of the beautiful Song Liling (Jin Ha) without realizing that "she" was a man. Because this is a memory play, Gallimard narrates his story from prison, having been arrested as a spy and having become the laughingstock of Parisian society. The irony of his absurd seduction is not lost on him, although it seems largely lost on Julie Taymor, judging by her direction. She undermines all the script's rich subtleties by adding a fatal dose of sentimentality: Cloying projections of butterflies fluttering at the end soften the conclusion, and Gallimard's self-knowledge turns cheesy and his death gory — a lapse in Butterfly's taste. The play's edge has dulled with time and with Taymor's direction; like the overlong Maoist production numbers, it creates a too-blatant tone.

Clive Owen, who usually plays sophisticated, smart and seductive characters, is here — appropriately — frumpy and befuddled, but his Gallimard lacks depth, the crucial tragic element, the longing of a little man for greater life.  Jin Ha is convincingly feminine and quite beautiful when s/he needs to be and convincingly crass when s/he isn't playacting. But it's not as if we've never seen drag queens before.

Basic to M. Butterfly is the duality basic to all theater — people pretending to be other people — a pleasure largely lost in the surprisingly dull revival.

At the Cort Theatre, 138 W. 48th St., New York.