When the founder of Cirque du Soleil, Guy Laliberté, says he's taken the thing back to its roots for its 20th creation, he doesn't mean street performance, still less holding out a hat. Stratospheric ticket prices mean that family groups are scarce most nights at the Albert Hall. And without the endorsement of children's laughter, the lame antics of the clowns, not to mention a man capering about in a shaggy dog suit, seem even lamer.
Kooza, created in 2007 but new to London, may fancy it harks back to a more innocent era of circus, but like the half dozen or so other Cirque shows that have made their way to Britain, it comes thick-coated in corporate gloss. The music, with its nonsense words, is so slick it's hard to believe it's live. The set, with its blow-up canopy that inflates before your eyes, is as opulent as a Rajah's palace. The engineering is jaw-dropping, vast pieces of kit manoeuvring in and out of the crowded Albert Hall roofspace with the ease of valet parking. Costumes and make-up are more fabulously detailed than can possibly register over the vast distances of the venue. Only if you buy the souvenir programme do you see that the faces of the entire troupe are gilded and decorated like Javanese puppets. Yet nowhere do you find the names of the artistes who are risking their necks.
Risk is the only heartfelt element in this enterprise. When a tiny woman with My Little Pony hair flips off her trapeze to effect a triple twizzle in freefall, there is only a thin, near-invisible clip-on cord between success and certain death. And when a small Thai man quietly builds a tower from 10 chairs, setting the last at an angle to balance on it one-handed, you note the care of his preparation. There's nothing to save him if he goes.
More heart-in-mouth moments occur as an acrobat strapped to a single stilt is fired 30 feet into the air, and when a pair of devil-horned toughies prowl the outer rim of "the wheel of death". These are no mere tricks, and in a show almost three hours long, with enough gurning to last a lifetime, you feel you've earned them. For all that Cirque du Soleil is credited with the invention of "new circus", its extravagance now puts it out of step with the times.
The London International Mime Festival is this year dominated by circus, if on a different scale. Ockham's Razor is a company of five aerialists whose work feels very fresh. Their latest piece, Not Until We Are Lost, is a promenade affair, the action playing out beside and above the milling spectators. At first, thrust into the black cube that is the new Platform Theatre behind King's Cross, one doesn't know where to look. Perhaps at the spotlit harpist plucking a golden clarsach in the corner?
When, suddenly, a bare foot appears by my ear, I realise I've unwittingly been leaning against a tall, glass chimney lined with paper, from which a person is scrabbling to emerge. Before long both she and the scrunched paper have comically disappeared, as if sucked down a waste disposal. It makes for a lively start. Major items of gym apparatus slowly come into focus. A giant rack provides a mountainside up which all five performers labour, hands and feet tied to their neighbour's – a test of amicable cooperation. Each then whooshes back downhill as if on the Cresta Run. A set of gym bars is the setting for a mini romcom, as two guys cajole a reluctant girl into playing their games. She eventually seems happy to let them swing her by the ankles, before goosing them with friendly mischief of her own.
Over it all, Graham Fitkin's music throws a glimmering veil, building to a tingling climax as harpist Ruth Wall overlays loops of her own playing. Equally joyous is the choral flashmob that breaks out in the dark. A magical show, from people with more than sawdust between the ears.
'Kooza' to 10 Feb (0845 401 5045); 'Not Until We Are Lost' tour (ockhamsrazor.co.uk) booking to 16 Jun. Mime Festival continues to 27 Jan
Kenneth MacMillan’s version of The Sleeping Beauty, to the original score by Tchaikovsky, is revived by English National Ballet under its new director Tamara Rojo, who stars in some performances. At London’s Coliseum to Saturday, then New Theatre, Oxford (19-23 Feb) and Southampton Mayflower (26 Feb-2 Mar).