THEATRE / Now you see it, now you don't: Paul Taylor on Robert Lepage's The Seven Streams of the River Ota, at the Edinburgh Festival

Eric Bentley once wrote regretfully of Orson Welles that, 'From the Boy Wonder, the wonder seems to have gone, if not the boyhood.' His remark kept popping into my mind while I was watching The Seven Streams of the River Ota, the latest work - or rather the first three parts of a work that is destined to grow into a seven-section epic - by Robert Lepage. The French Canadian director is par excellence the sort of artist who will still be inviting the description 'wunderkind' when he is well into his forties.

The publicity gave advance notice that this was a piece that would follow in the footsteps of The Dragons' Trilogy (1985-1991) and Tectonic Plates (1989-92), Lepage's vast, multi-dimensional stage-poems which unfolded as a sort of shifting visual palimpsest - motivically uncovering the image behind the image behind the image, the layer under the layer, in order to trace the hidden, dream- like connections between objects sundered in space and time.

True, the overarching themes could be all-embracing to the point of vacuousness: what kept you gripped was the protean specificity of the illustration. In Tectonic Plates, for example, the geological process of continental drift was used as a metaphor for human separation and reunion, a subject that doesn't exactly come bristling with constraints. The result, though, beguiled away most of your doubts in the playful poetry of its linked sunderings and mergings - whether from the global perspective, as grand pianos, representing long-estranged continents, fitted together into each other like jigsaw pieces, or from the cultural angle, as coincidences, like the fact that Chopin and Jim Morrison are buried in the same Paris cemetery, spawned correspondence between revolutions in the 19th century and the 1960s. As with much of Lepage's work, you had the illusion, as you watched the melting metamorphoses and weird intersections (a hippie suicide, say, coalescing with Delacroix's portrait of the drowned Ophelia) of being made privy to the secret patterns of chance and fate.

Even here, though, you couldn't quite quell the suspicion that, in so far as the piece had an intellectual structure, it was a suspect one. To link the processes of human life to continental drift does not, to say the least, pay tribute to man's capacity for purposive, rational action. But then the impressionistic reverie of Tectonic Plates was calculated to be proof to such objections: you can contradict an argument, it seemed to be saying, but you can't contradict a dream.

With Seven Streams, Lepage moves into an area where misgivings about his methods begin, for me, to intensify. The Ota is the river that runs through Hiroshima, which is where the play is mostly set, in the Japanese home of Jana (Ghislaine Vincent), a 60- year-old Jewish-Czech photographer, whose roving flashed-back- to experiences are meant to add up to a paradigmatic 20th-century journey. The piece, underscored with kabuki-style groaning noises and percussion, has a prologue performed by bunraku puppets, which links the advent of pyrotechnical means of destruction with perverted desire. Feudal court scientists, in this fable, accidentally hit on gunpowder while attempting to concoct an aphrodisiac for the aged, repulsive emperor who has kidnapped a lovely, but resistant young girl.

Though eroticism and infidelity continue to surface throughout, it is survival, rather than the technological devastation for which the place is a byword, that preoccupies Seven Streams. And it's when exploring this theme that Lepage's theatrical wizardry is in debatable taste and in danger of distortion. Mirrors are a recurring motif, from the hand-mirror with which the girl shows the emperor his ugliness, to Jana's memories of being interned as a girl in a Nazi camp. As she gazes at her 60-year-old self in her bedroom mirror, it suddenly sends back an image of herself at 11, and of the remembered camp as an infinite regression of mirror-on-mirror reflections.

It turns out that, while she was there, she took part in a cabaret, playing a magician's assistant who 'vanishes' from the box by crouching behind the mirror. 'Are all the people who disappear hidden behind mirrors?' she asks the conjuror plaintively, thinking of her mother, father and brother. If he knows the trick of it, can't he make them reappear? What eventually destroys the poignancy of this is that it's by just such tricksy means that Jana herself escapes, rolled away, ensconced behind the magician's mirrored box, by an unwitting Nazi. But how can her survival have any representative dignity or truth, if it's achieved by sleight of hand on Lepage's part?

When she is translated to 1970s New York (where her squalid bohemian lodgings are wittily evoked by a bathroom that's literally 'shared', with a variety of self-absorbed oddballs using it at the same time) we see at one point that she has been shooting up. But how she conquers the drugs habit is as serenely glossed over as how she got out of the camp. The transition between then and the play's present is realised courtesy of a stunt. While the younger self (Marie Brassard) is lying exhausted and depressed in the bath, the 60- year-old Jana simply pops up and lets her slide down the plughole. Nice picture, glib evasion. Her status as a semi-magical construct lets Lepage off the hook of really imagining what it's like to have gone through what she has endured, given that she has only sort of gone through it. You just wish the rest of Lepage could catch up with the peerless pictorialist.

Of the other characters, Ada (Rebecca Blankenship) is the thinly realised and creakily introduced daughter of a friend and protector of Jana's who committed suicide in the camp. Jana's young French- Canadian lodger / lover (Eric Bernier), his former girlfriend, and the couple from the Canadian embassy in Hiroshima provide sexual farce and a burst of quite amusing if sub-Richard Nelson comedy of cultural tension in the third part. But the acting, especially earlier in the evening, had the international stiltedness of a certain type of porn movie, and technically the show was far from ready. In droll tribute to his whirling feats in a harness in Needles and Opium, Ken Campbell once referred to Lepage as 'the dangling French-Canadian'. After this very slow (though obviously cut) and inconclusive effort, perhaps we should change that to 'the dawdling and doodling French- Canadian'.

At the Meadowbank Sports Centre, Edinburgh to 21 August (Booking: 031-225 5756)

Sponsored by Scottish & Newcastle

(Photograph omitted)