Dance: Highland springs

Scottish Ballet Sadler's Wells, London Tango Pasin Lyric, London

Scottish Ballet has been through the mill these last few years. Rocked by crisis after crisis, it has had to justify its very existence. Does Scotland really need its own classical dance company? For an answer, one could canvas the far-flung highlands and islands which the company takes pains to visit every year. Or measure the applause at Sadler's Wells last Thursday when it made its first London appearance in 20 years. Stylish, dynamic and hugely ambitious, this outfit bears every sign of becoming a major national asset.

The ambition showed in the choice of programme, beginning with a rare revival of Kenneth MacMillan's Diversions - one of the few plotless works he made and thus, to me, one of the less appealing, despite technical demands which range from the punishing to the downright fiendish. The company seemed more at ease with the tangible emotion swashing around Lila York's Rapture, an extravagant half-hour on the theme of dying and going to heaven. Perhaps only an American could get away with this - but she does, with a pinch of schmaltz and a heavy dose of pizazz.

It's a nebulous opening, limbs rising slowly through murk, like corpses erupting from a graveyard, but then things hot up big time. Air-wheeling figures romp in long diagonals across the stage, boys leap like spring lambs, toes scissoring up to touch foreheads; girls sprint and skid in long, joyful arcs. The score, a grand patchwork of Prokofiev piano concertos, keeps up a cracking pace thanks to pianist Lynda Cochrane and a terrific orchestra which I presumed to be Scottish Ballet's own. The slow movement summons visions of death and decay, then joy breaks out in more teeming upward motion, ending in a crowded tableau like a fully-opened sunflower. Impossible optimism, hopeless escapism, but that's what ballet does so well.

The meat of the evening should have been the commission from Tim Rushton, a young British choreographer based in Denmark, but nIghT LiFe (does he need a new typewriter?) turned out to have more style than content. This must be the first ever dance work inspired by a chat room on the Internet. It also claims to reflect the life of Glasgow's clubbers, though these characters looked rather too Vogueish to have spent many nights on the tiles.

The plot is touchingly naive. Girl seeks good time, finds only poseurs and gropers. Girl tries a bit harder, finds boy, and labours to establish a bond, unknown in this world of instant thrills. They kiss. The end. Lez Brotherston's set is a major plus - a series of elegant white prosceniums which take on luscious hints of mauve and grey and cream - and so is the music: not the ear-slamming dub you expect, but Bach at his most sublime. The mood is restrained, the movement modish and easy-on-the-eye, but ultimately rather shallow. All praise though, to the central couple, Lorna Scott and Ivan Dinev, who give gorgeous suppleness and clarity right to the final clinch.

The mating game is also sole focus of the latest Argentine tango show to arrive in London. The difference is that these couples have steam coming out of their ears. Tango Pasin takes on the cabaret format we've come to expect of theatre-tango: cafe tables, a fruity 50-a-day singer, an orchestra of jowly old men who draw astoundingly virile sounds from squeeze box and fiddle, and dancing couples whose major achievement - once you've got over their slicing speed and prowess - is to make you believe they are ready to rut at the drop of a well-dented fedora.

Over the course of two hours you think you get to know these spangly couples and their not-so-private fancies. There's the Dan Dare who appears to crush his partner with his massive bulk while she jabs at him with spike heels; there's the foxy modern duo who go in for tricksy aerial leg-splits, and there's the loping Thirties cove with the air of Robert Donat in The Thirty-Nine Steps with the girl who sports a series of amazing spray-on dresses. I swear I have never seen so many variations on a pencil skirt as appear in this show - sequinned, lamed, tasselled. The only uniform feature is that important split to the hip to let the scissor- legs do their stuff.

Tango, born in the slums of Buenos Aires, has an intriguing history, but like every other tango show we've seen, Tango Pasin fudges it with a brief nod to "the olden days" (a skit in bustles and bonnets) before moving on to a titillating mish-mash of nowadays. Will someone please devise a show which highlights the great dances that went into this urban melting pot: the milonga, say, and the candombe, and the habanera, followed by a step-by-step expose of tango from 1890 to the present. Now that would be a show to get passionate about.

'Tango Pasin': Lyric, W1 (0171 494 5045) to early August