Moby Dan

The basic conceit of Moby Dan, the first part of a three-play festival from the much-loved Barabbas company, is that of an imaginary ocean voyage in a paper boat. The show has to steer a course between the childlike and the childish, between the delightfully whimsical and the merely twee. When the wind is behind it, the journey is exhilarating. When it dies down, the show drifts into shallows and doldrums.

The good news is that Barabbas is negotiating the awkward transition from its founding energies to a long-term future with style and grace. None of the three actors who founded the company in 1994 is on stage here, though Veronica Coburn wrote and directs Moby Dan and Raymond Keane is artistic director. (Mikel Murfi has moved on.) Yet the distinctive Barabbas techniques, drawn from traditional clowning and the Jacques Lecoq school in Paris, are confidently embodied in the cast. In the best Barabbas traditions, they combine the stylised methods of red nose clowning and mime with the creation of sharp, realistic characters. The five job-seekers on a "community-based rural renewal programme" who end up accidentally locked into a town hall overnight are, for all the fantastic elements of the show, utterly credible. Lynn Cahill's sour middle-aged widow, Deirdre Molloy's small-town cowgirl and her gormless twin, Eric Lacey, Ruth Lehane's florid Catalan and Daniel Guinnane's drippy hippy, all have recognisable faces behind their red noses.

The closer the show stays to this reality, indeed, the funnier are the antics. The first half of the show, in which the characters are wittily introduced and the notion of acting out a version of Moby Dick takes hold, is completely convincing. The element of realism provides enough fuel to push the boat into the clear blue water of pure invention. Carol Betera's wonderful designs give delightful substance to the wild notions that begin to flow.

The energy, though, comes from the most dangerous, if thrilling, source: the feeling that what happens next is anybody's guess. There is no sense that Moby Dick is a necessary myth for these people, no feeling of inevitability. The search for the great white whale remains an external conceit rather than a shaping metaphor.

What this means is that when the invention flags, as it does in the second half, there is nothing left to drive the show forward. Sex and drugs provide momentary distractions, but the feeling that nothing is really at stake here becomes ever stronger. The action begins to feel like an old episode of Bosco, where the sense of make-believe is sustained only by an insistence that good boys and girls would never be so rude as to give way to scepticism.

The overall feeling, then, is not of a bad show, but of lots of good things spread too thinly. Like the whale itself, there are thrilling glints of something awesome, and a lot of blubber.