DANCE / Underwater group therapy: Judith Mackrell reviews DV8's Strange Fruit at the Riverside Studios

DV8'S latest piece, Strange Fish, is about the tyranny of couples and groups, about the pain of not belonging and the terror of being alone. It is both pitiless and profoundly compassionate. It is harrowing and frightening. It is also the funniest piece that the company (directed as always by Lloyd Newson) has ever made.

Visually it is stunning too, with Peter J Davison's monumental wooden set containing cubby holes, doors and footholes that allow the performers to make a number of startling and perilous entrances. As the piece progresses, the opening up of a subterranean water tank beneath the floor, and the unfastening of a trapdoor which unleashes a torrent of white rocks, create even more extraordinary stage pictures - images of stark, elemental chaos that give a Tarkovskian resonance to the unfolding of the relationships on stage.

These begin with two women, Lauren Potter and Wendy Houstoun, who appear bound together by the intense gang rituals shared by young girls. They communicate through sign language, giggle at secret jokes and twitch with a wicked mutual hysteria. Two men enter to become objects of their fascinated and flirtatious contempt. Yet to Houstoun's confusion, Potter starts seriously romancing with one (Jordi Cortes Molina) and the loyalty of friendship gives way effortlessly before the glamour of sex.

Houstoun remains an outsider throughout the piece, finally embracing her independence but not before she has clownishly attempted to infiltrate the closed world of couples. There's some hilarious and hair-raising dance as Potter and Molina lie embracing on a bench and Houston tries to get between them. The whole struggle accelerates into a wild quartet of ducking and throwing as bodies and furniture fly hectically around the stage. Houstoun has a go at sex herself, but is vividly and comically distressed by the whole business of undressing in front of her mate (Dale Tanner). Her sense of failure becomes abject as she finds herself lying numbly beneath Tanner's insensitively pounding butt, and she slips herself away to perform a punishing and purifying dance amongst the mercifully inhuman pile of rocks.

Her partner in isolation is Nigel Charnock, who makes his first brilliant and appalling appearance during a party scene. His whole body is eloquent with unease and anticipated rejection and, in a hyperactive gabble, lets fly a volley of social platitudes which send everybody racing for cover.

It is possible to see him and Houstoun as two gays forging a lonely alliance in a world of heterosexual couples, yet the work's exploration of alienation is subtler than that. There is one terrifying scene, for instance, that shows what happens when nice people taste the power of a group in which Diana Payne-Myers (age 63 and cast as a lone eccentric) is picked on and spun giddily through the air by four younger dancers who cheerfully ignore her panic.

Houstoun and Charnock try to protect her but they aren't saints themselves. Houstoun is as unwilling to be caught with Charnock at the party as anyone else and he is thrilled to join the crowd who gossip viciously about Houstoun's sexual humiliation. Equally the two couples in the piece aren't cast simply as callous insiders. The joy of Potter and Molina in their new-found intimacy is real and radiant, the attraction between Tanner and his woman is palpable.

Parallel to the presence of social and sexual need is the siren lure of religion. The singer Melanie Pappenheim is cast as a female Christ who hangs from a cross while singing potent and seductive liturgical songs (specially composed by Jocelyn Pook). Towards the close when a battered Dale Tanner seeks release from whatever life dealt him, she cradles and blesses him with water - allowing him literally to give up the struggle. And it is a mark of the determinedly independent road which Houstoun elects to tread that she climbs the cross to give Pappenheim a long, and secular, kiss - on the strength of which the latter collapses in a heap both as woman and symbol.

As in all of DV8's work, the performers in Strange Fish take astounding and humbling risks. As dancers they are audacious in fashioning metaphors of extreme emotion - Charnock leaping from a high platform to launch himself on some independent life; Payne-Myers clinging grimly to Tanner's shoulders as she's wheeled through space; Houstoun leaping recklessly into the tank of water that symbolises her willingness to taste the unknown. At the same time it is clear that all eight members of the cast are drawing dangerously on their own experience - stripping themselves naked, both in their pleasure and pain. This is a piece that dares to address intense and gruelling areas of our spiritual and emotional life and, immaculately directed and performed as it is, it ranks as one of the richest and most unsparing theatrical experiences I've had in a long time.

Continues until 8 August at the Riverside Studios (Box office: 081-748 3354).