The Forsythe Company, Sadler's Wells, London <br></br> Random/John Tavener, Sadler's Wells, London

After 20 years as a beacon of daring programme policy (everything they did was avant garde, with the city council's blessing) the company was disbanded last year amid howls of recrimination. Half the dancers loyally followed Forsythe into this new venture, but on the evidence presented here, the typically extravagant Forsythe repertoire hasn't made the cut. Of the four works shown none uses costumes, half have no music and only one makes a nod at set design. In other words Forsythe has scaled down. The crucial question is whether the impact is the same, and the answer, not surprisingly, is no.

In The Room As It Was the live mouth noises provide a certain drama as fists swing out, legs buckle and crumple, and feet look as if they've been put on the wrong way round. A similar dislocation pervades NNNN, a quartet for four likeable scruffs who seem intent on forming a dense line of defence - something like the wall of male flesh in a rugger match - but keep discovering some new weak point. When a knee, shoulder or head fails to perform, the whole structure falls apart and the process of tugging, smacking, up-ending and de-tangling starts again, producing some amusing moments, but not enough to count as comic. At times Forsythe seems more intent on working out a theory than supplying us with theatre.

Of Any If And employs the old Forsythe hallmarks of grand spectacle and even grander metaphor. The piece opens in a charcoal gloom with undecipherable whispering from two readers seated onstage. When a vast steel rig descends bearing placards of random words like fridge magnets, one feels compelled make sense of them. Yet though the rig falls and rises scores of times while a whiplash duet goes on below it, the words remain jumbled. I think if I'd read the line "out ... fallen has ... thunder", once more I'd have started to gibber. The piece was created by Forsythe just after the loss of his wife to cancer, and as an expression of incoherent rage and impotence I grant it may have a glimmer of a point. But I think I am being generous. The piece made me want to run.

The Forsythe everyone was waiting for finally surfaced in One Flat Thing. At least in this case it was obvious that the flat thing was a table, only there were 20 of them, dragged with a deafening roar to the front of the stage to become a platform-cum-obstacle-course for vaulting over, slithering under, sliding, hopping and rolling between, all at neck-jarring speeds to Thom Willems' car-crash score. Forsythe may not have brought us new work, he may have dumped any idea of glamour, he may well be looking up his own bottom, but this great yelp of energy redeems him.

Wayne McGregor is Britain's nearest answer to William Forsythe if only in that his distinct, madly fast, wiggly-worm style was developed from the way his own body operates. Like Forsythe, too, McGregor has pursued single ideas with a thoroughness that can leave his audience begging for mercy. McGregor's schtick is science: first the brave new world of technology, now the mechanics of the human body. His latest work Amu - meaning "of the heart" in Arabic - was conceived with input from two heart-imaging specialists from the Brompton Hospital, though I somehow doubt that the choreography itself, removed from the suggestive influence of music and stage effects, would suggest anything more than a group of people exercising their arms and legs in bizarrely complicated ways.

But McGregor's efforts hitch a giant ride on the luxuriant vocal and orchestral music of Sir John Tavener, no stranger himself to the cardiac departments of Britain's hospitals, and a fervent believer in what he calls the "cosmic heartbeat". The two artists make the oddest pair, and there is a sense in which neither dance element nor music much impinges on the other. While Tavener's singers (magnificent, all) are bent on telling a Sufi love story, McGregor's dancers merely respond to the general emotional throb. The true star of the show is lighting designer Lucy Carter, whose ability to pull heart-stopping effects from her box of tricks knows no limit. But all three artists climax together in the final moments as the voices trail away, the air turns misty grey, and bodies levitate into the ether, leaving only the sound of a beating heart.

jenny.gilbert@independent.co.uk