Naked, Sadler's Wells, London

Affairs of the heart laid bare

Naked is the Ballet Boyz' first full-evening show, their second stab at choreography. This time, dancers William Trevitt and Michael Nunn have dropped the video diaries, stopped sweet-talking the audience between numbers, and turned to narrative. Naked tells an adultery story, at first in hints and implications. Plotting, and dance, become tauter and bolder as the work continues. The first half meanders; the final confrontations are gripping.

Naked is the Ballet Boyz' first full-evening show, their second stab at choreography. This time, dancers William Trevitt and Michael Nunn have dropped the video diaries, stopped sweet-talking the audience between numbers, and turned to narrative. Naked tells an adultery story, at first in hints and implications. Plotting, and dance, become tauter and bolder as the work continues. The first half meanders; the final confrontations are gripping.

Bob Crowley's set design is a white box of a room - a bedroom or hotel room. Window curtains move in a breeze. Daylight comes and goes in Paule Constable's beautiful lighting. The six dancers are dressed for a summer party, men in shirts and trousers, women in heels and floaty dresses.

At first the choreography is floaty, too. The Boyz' company, George Piper Dances, has several works by choreographer Russell Maliphant. He's helped to define their style, and Trevitt and Nunn cite him as their choreographic consultant. They use the same flowing vocabulary, with swung arms and curling turns. It isn't taut enough.

Emotions bring the performance into focus. With the Royal Ballet, Trevitt and Nunn danced a range of dramatic works. They're used to projecting feeling, and both have considerable stage presence.

In one duet, Nunn takes Monica Zamora's arm, and she slips from his grasp. They convey a whole relationship in how they stand, in glances caught or evaded. Zamora's discomfort is in her tense shoulders, her hasty step away. Nunn's demands give his partnering a pugnacious edge.

Oxana Panchenko stalks through, cool and independent, leaving Trevitt behind. A third couple, danced by newcomers Yvette Halfhide and Thomas Linecar, are less well defined. Hugo Glendinning's video projections loom on the back wall: filmed dancers walk out while the real dancers stay. Sometimes they overshadow the stage action.

This first act is too full of drifting incident. The music goes from atmospheric electronica to Doris Day's "Perhaps, Perhaps, Perhaps". Looking back, it's clear that Zamora must be considering an affair with Trevitt: the song is speaking for her. At the time, the scene isn't clear. It's a fluffy interlude, a girly number danced by the women. They might be sharing confidences, they might just be dancing. More needs to happen, in steps and in drama.

At last, Zamora takes off her heeled shoes and launches into a duet with Trevitt. After all that drifting, this couple look bold, sexually assured and compelling. She curls against him, very close and physically relaxed, then arches swiftly into a swooping lift.

The second half is darker, filled with threat and consequences. The white room has vanished, replaced by a dark set lit in pools of shadow by Michael Hulls. Projections of Zamora and Trevitt glow hypnotically on the walls, in and out of focus. The film breaks up in static as Nunn begins a tight, jealous solo, all thrusting lines and angry tension.

Panchenko grieves to another girly number, Patsy Cline's "Three Cigarettes in an Ashtray". This is a woman lamenting her lost lover, but on stage the tone is uncertain. Panchenko dances in clean, stark lines, but we don't take her suffering seriously when the soundtrack is so kitsch.

Naked ends with its most powerful dance. Zamora, Trevitt and Nunn circle each other warily, building up to a confrontation. On the wall behind them, a clock starts a countdown. The movement is prowling and angry. These dancers generate currents of feeling, a shifting sense of betrayal and threatened revenge. That ending lifts the whole performance.

As choreographers, Trevitt and Nunn are still feeling their way. They're already gifted stage directors. The design and dramatic direction show a sure sense of theatre. Their own performances pull it into dramatic focus.

To 11 June (0870 737 7737), then touring (see www.gpdances.com)