Last year William Forsythe quit after two decades with the Frankfurt Ballet, the troupe he directed and for which he made dance works that pushed the boundaries of movement to extreme limits. Those works won, for the company and for Forsythe, both huge enthusiasm and no less huge incomprehension. In January this year he established his own ensemble, one naturally devoted to his own aesthetic, and last week The Forsythe Company had a brief London season.

What we saw was, I suppose, today's essential Forsythe - gritty offerings of dance disjunct, derailed, denying any of the conventions of balletic presentation, yet offering traces of balletic manner and language (though these traces are faint, save to the eye of the true believer).

Watching this parade of bellicose, unrelenting angst, performed by 18 dancers who had the unseeing air of fanatics and wore the sort of clothes associated with clearing out the garage, I remembered with some regret the Forsythe of Pas/Parts, the study he madefor the Paris Opéra troupe a few years ago, in which a developed academic manner, dazzlingly conceived, produced dazzling results.The four pieces in this Sadler's Wells programme, made within the past10 years, showed Forsythe at his most introspective, most rigorously unyielding in means, and (I find) most uncommunicative.

The four men in N.N.N.N - all titles are incomprehen-sible - exchange and develop fragments of activity, with legs, arms, heads, feet going their own cussed way. Dance has lately been introduced into certain prisons here, and is serving admirably to help prisoners express themselves and understand their condition. N.N.N.N looks to me a perfect example of this therapy.

With The Room as it Was, seven dancers gasped and made emotional and physical moves on each other.Of Any If And, a supple duet eeling about the stage, was decorated, shall we say,with the faintest sussurations from two people whispering a text while alighting gantry rose and occasionally descended, bearing on it assorted words on giant fridge-magnet cards.

The ritual abyss of the evening came at the end with One Flat Thing, reproduced (sic), in which the company, plus 20 steel tables, raged and romped like drunk children, while a soundtrack by Thom Willems evoked a turbine with dysentery.

This may be Forsythe's Kingdom of the Shades, but it shows his creativity atits most self-conscious,most obsessive, most alienating. Two things are remark-able: the impeccable timingof the cast in playing toeach other, and the way in which these works reflecta society where declining social manners are matched by aggression, private and political. If you still needto know what is wrongwith our world, Forsythe's dances are no bad guide.