George Piper Dances, Sadler's Wells, London

This bill gets its four stars for Christopher Wheeldon's Mesmerics. In two years, Michael Nunn and William Trevitt have commissioned a lot of new dances, and this is the best I've seen. Nunn and Trevitt are the Ballet Boyz, made famous by their television video diaries, and they use that celebrity to win audiences for a hardworking dance company specialising in small-scale pieces by living choreographers. Here, their programme is a mixed bag, but the Wheeldon really works.

Mesmerics is a highly patterned ballet, all echoes and reflections. Its Philip Glass score is full of repetitions, too, but Wheeldon doesn't follow them; his fluid dance sits on the pulse of the music, not its building-block phrases.

The real surprise is the depth of the stage picture. Dancers are set in lines that slice across the space; Wheeldon builds floor patterns with only five dancers. One bending, swaying duet is shadowed by a second pair, who slip into variations on the first couple's theme. It's Wheeldon's sense of placing and dynamics, not the size of the stage, that makes those couples look so far apart. In another duet Nunn and Trevitt mirror each other face to face, some distance apart. Their movements are all sideways: a crablike shuffle as they edge through curving floor patterns. Another sequence is full of circling arms: when a line of dancers do that in canon, you see circle on circle, whirling in both directions at once.

Wheeldon also picks up the company's classical and contemporary sides. The balletic Trevitt is cast in bendy steps; the chunkier Nunn produces clean classical line. The movement is always soft and clear.

Don't expect softness from William Forsythe. Approximate Sonata I, V is one of his joint-popping duets, bleakly lit and broken up with dialogue. It's a version made for George Piper: two duets from a 1996 ballet reworked on Trevitt and Oxana Panchenko. We start with Trevitt walking, pulling faces, changing position in response to an offstage voice. It may be a comment on dancerly obedience in rehearsal, but so what? The duets themselves are fast, off-balance, extreme. Trevitt and Panchenko are certainly well up to speed, but the dance is monotonously harsh.

The Ballet Boyz have always used film to introduce the dances, to cover scene changes, to keep the evening moving. As their programmes get longer, there's less need for the video, especially when they stick to cute travelogues. Audiences enjoy watching Trevitt practise Forsythe moves in his bath, but it doesn't match the Boyz' earlier film of choreographers at work. The only choreographer here is Cathy Marston, explaining that her aimless duet for Panchenko and Monica Zamora was inspired by Ophelia and Lady Macbeth.

The evening ends with Critical Mass, now a signature piece for the Ballet Boyz. Russell Maliphant's duet makes a good image of George Piper Dances - the two men trying out dance styles, taking each other's weight - but the metaphor's better than the steps.