Hath not a Jew a mobile phone?

IT'S NOT difficult to work out the logic behind Peter Zadek's decision to float The Merchant of Venice on the open market. By setting his production for the Berliner Ensemble in the glass-panelled courtyard of a corporate building, and replacing Venetian traders with FT-toting, Armani-suited city dealers, he means to give Shakespeare's most difficult play a razor-sharp contemporary edge.

We are presented with a Shylock who is fully assimilated into the malicious gentile commercial world around him: "Hath not a Jew blue eyes, blond hair and a mobile phone?" might have been a more fitting epigram for conspicuously un-Jewish actor Gert Voss's hybrid creation. The character's religious identity is subordinated to his financial muscle: the wager with Antonio is joyously undertaken in the spirit of a Nick Leeson commercial venture, with both men revelling in the resulting hot rush of adrenalin.

But as so often seems to be the case - Zadek, the son of Jewish fugitives who settled seamlessly into rural Wales, probably knows this all too well - retribution comes in the form of the next generation. Jessica now betrays her father because of the family's cultural disorientation. At the end of the play, he is not the victim of Christian viciousness, but of the denial of his Jewishness. These days assimilation is a cultural crime second only to fascist collaboration.

All this might be wonderful, radiantly radical stuff - if it worked dramatically. Zadek's production is emaciated and empty, relying far too often on intellectual signposts and inference that make little mark on Shakespeare's familiar anti-semitic rant. Gert Voss begins with a powerful, ebullient Shylock but is forced to switch off his performance in the court scene when the interpretation runs out of steam. Present- ed almost like a flat, rehearsed reading, the scene which exposes Shylock's hunger for his pound of flesh is exponentially more vicious - to the extent that members of the audience yelped with joy at the news of his forced conversion to Christianity. This is not, presumably, quite what Zadek intended.

Other aspects of the production don't help: a terrifically gaudy backdrop, 1980s power costumes, and some lame, impromptu banter.

The inclusion with every ticket of an English translation of Bernard Marie Koltes's Dans la Solitude des Champs de Coton may have seemed a good idea - no distracting surtitles, no aching neck muscles - but could have backfired. Audiences might have been stranded in the second tortuous paragraph, or not have turned up at all for Patrice Chereau's downbeat but intensely absorbing production.

On the page, much of the work seems incomprehensible and indigestible, a philosophical treatise hung on the rickety framework of an evening meeting between two anonymous individuals: the Dealer and the Client. Koltes has produced some brilliant work - Roberto Zucco, the play about an Italian serial killer he wrote when he was dying of Aids in 1989, has become a French classic. But Dans la Solitude, which deals obliquely with emotional barter and the way people remain in emotional limbo because few are honest enough to reveal what they want to buy or sell, seems obscure and forbidding. "The only frontier left is the one between buyer and seller," proclaims the dealer. "An unmarked territory where each holds the desire and the object of desire all at once, hidden and revealed."

It is only in the shabby auditorium of the Drill Hall, confronted by designer Richard Peduzzi's asphalt arena, that the music of Koltes's poetic language is revealed. Both Chereau, who plays the dealer, and the scintillating Pascal Greggory (last seen in Chereau's film La Reine Margot) are vocally impeccable, swooping along each cadence and perfectly sustaining every melodic line. A murky psychological drama is woven around the bare bones of the text, with the two men prowling around, periodically lunging at each other. Their gladiatorial sparring is underscored by piercing followspots, by electronic groans and grumbles lurking in the corners of the sound system, and by a number of unexpected rest periods which explode into bizarre, eccentric, electrifying dances.

That the production survives Chereau's stage inexperience - his performance occasionally seemed as if trapped in a nerve in his neck - is a tribute to his skill as a director, his ability to amplify minute sensations until they fill the vast auditorium, and to his unshakeable faith in the work of Koltes, a writer he discovered, nurtured and continues to champion.

The French company Deschamps et Deschamps, who brought their latest work C'est Magnifique to the Playhouse, deliver more of the same, high-quality, perfectly timed, spectacularly choreographed but essentially unengaging farce. Centred around the shambolic renovation of a run-down bar, it ambles through a succession of spectacular and absurd routines: long-distance plate juggling, furniture abuse and other gems of symphonic slapstick. Some moments are sublime: Yolande Moreau sings the plaintive title love song while sporadically shuddering into a bizarre convulsive dance. But without any emotional points of contact whatsoever, this brilliance remains dry and purely technical.