La La La Human Steps, Sadler's Wells, London<br />Tango Por Dos, Peacock Theatre, London

Obsessive, compulsive, and thoroughly disordered

Back in the 1980s, while Michael Clark was re-defining ballet in man-corsets and Union Jacks, Canada had its own iconoclast in Edouard Lock. Hooking up to the fashion zeitgeist, Lock re-imagined dance as an amphetamine hit, crackling through the classical positions at vision-blurring speed.

Eight years after his last visit, Lock is back for a UK tour, with his Montreal-based company La La La Human Steps somewhat changed. His former muse, the wild-haired kamikaze-on-point Louise Lecavalier, has moved on to other things (no doubt on the orders of her chiropractor), and in her place are a posse of chic ballet girls in black leotards so brutally exposing that you could hang your coat on their iliac crests.

Deconstruction, if not destruction, is still high on Lock's agenda. In Amjad (a gender-ambiguous Arabic name), he proceeds to pixillate the best-known ballet classics into a fevered, fragmented, ungendered dream. Swan Lake is his main target. As he says in a programme note: almost everyone carries some mental image of that ballet, even if they've never actually seen it. And, yes, it's impossible to miss the iconic arm movements of Lock's bird-women, as they exercise them in different ways (a bit like windscreen wipers as they switch between insistent, fast and frantic). But oh dear, they do go on.

Where the real Swan Lake is a perfect marriage of physical form and poetic content, with a narrative, however unbelievable, holding it all together, Lock's fidgety, repetitive treatment feels like a needle stuck in a groove. Prevented from moving forward, it flaps and frets. The dancers' 100mph technique is dazzling, but to little purpose.

The chief pleasure for me was Amjad's (live) original music, a reimagining for piano quartet of the familiar Tchaikovsky score that ingeniously references its melodies and harmonic structures without ever quoting. With the order of the music randomly reshuffled, the listener feels both beguiled and benighted, which was clearly Lock's overall plan, as screens project images of crumpled sheets, blood-red feathers, and a tangled forest – a frequent 19th-century allegory for the unconscious mind.

On stage, the accelerated movements, the mechanical repetitions, the way the women seem to push away from and pull towards their partners both at once – all say something about modern neuroses, the contradictions of modern life, as well as its speed, but you get the point very quickly and there's still an hour to go.

For speed, style and – oh joy – woman-shaped women, my money is on Tango Por Dos, back at the Peacock Theatre with a new title. After a dodgy couple of visits, Buenos Aires Tango shows the franchise back at its best, the focus restored to the dance itself, and the sheer variety with which a sequence of varyingly amorous couples can exploit it. The men devastatingly dapper in suits, the women exquisitely, er, sheathed, you forget that men were ever from Mars or women from Venus. This ardent body language and flickering, sparring, truly dangerous footwork is playful and predatory on both sides.

'Amjad': tour details at 'Buenos Aires Tango': Peacock Theatre (0844 412 4300) to 23 February