Peter Sellars is one of the most interesting stage directors now active in opera. His productions frequently show new dimensions and unsuspected depths in works that have been supposedly familiar for a century or two. But he should leave the hype about his productions to someone else.

In this week's "Great Performance" (tomorrow, 2:30 p.m., WETA, Channel 26), he shows more talent for expressing the inner tensions of Mozart's "Cosi fan tutte" ("Women are all alike") visually than for explaining them verbally. The staging brilliantly reflects and justifies his assertion that the almost abstract characters in this intricately balanced work are "real people," not -- as previous generations thought -- symbolic elements in a sort of elegant equation.

He makes quite clear his view that eros, not a philosophical question, is what this opera is about, and he gives a strong visual treatment to the psychological dark side of "Cosi." This may be the opera's most fascinating element, and it has not been much explored until the last generation. But his pre-program pitch oversells the opera.

"Is this the most offensive anti-feminist opera ever written?" he asks, "or an exploration of the outer weird edge of the human psyche?" It can be both, of course, and under his direction it is, but competition is fierce in the anti-feminist department, with Mozart's "Magic Flute" among the front-runners. "Cosi" deals with the question of whether women are naturally fickle, but, whether or not Mozart and his librettist Lorenzo da Ponte realized or intended it, male chauvinist stereotypes are hit as hard as feminine inconstancy. The measures used by the men to test the women's fidelity involve blatant deception and extreme psychological harassment. Sellars shows this without pulling punches. All six of his characters have symptoms of serious mental instability.

The performance was taped in December and is set in the present; Guglielmo (James Maddalena) and Ferrando (Frank Kelley) are Naval Reserve officers who pretend to be called to action in the Persian Gulf, then return in disguise to test their fiancees' fidelity.

The action takes place in "Despina's Diner by the Sea," a greasy-spoon restaurant somewhere near New York; Alfonso (Sanford Sylvan), who makes a bet with the two young men about women's fidelity, reads the New York Post, clearly implying that he is not a philosopher. In this "Cosi," he is an embittered, cynical Vietnam veteran. Sellars suggests that his bitterness may be motivated, at least in part, by his masochistic relationship with the waitress Despina (Sue Ellen Kuzma), who actually mounts him like a horse during one of her arias. This is a radical departure from the usual treatment of these characters, but it is interesting and some justification can be found in the text.

The pivotal characters in "Cosi" (which really has no secondary roles) are the sisters Fiordiligi (Susan Larson) and Dorabella (Janice Felty), whose fidelity is sorely tested and finally cracks. Both roles are beautifully sung and acted in a production that features finely calibrated ensemble work with a cast that shows no weaknesses. In an audio recording, the music (what we might call conductor Craig Smith's "Cosi") would stand up very well, though it would be quite a different experience from Sellars's "Cosi." One weakness is the almost meaningless visual noodling that often happens during da capo arias while the music elegantly repeats itself.

One inaccuracy in Sellars's pitch should not go uncorrected. He talks ("Amadeus"-style) about an aristocratic plot against Mozart: "The greatest composer who had ever lived at this point, the composer who was more capable of working with large-scale forms than any composer in the history of music, spent the rest of his career in Vienna being commissioned to write two-minute pieces. They wanted to kill him and, of course, he died soon after." This may be emotionally true; Mozart did fall out of favor, wrote a lot of short pieces in his last year and died young. But he died of natural causes. One could argue forever about whether he was "greater" than Bach, more capable of handling large forms than Monteverdi, Bach, Handel and Haydn. But the "two-minute pieces" with which he ended his career after "Cosi" included the operas "La Clemenza di Tito" and "The Magic Flute," the Clarinet Concerto, a lot of extraordinary chamber music and the unfinished but magnificent Requiem.