The first doubt hits you right away: six figures, all with their backs to the audience and all wearing hoodies - who's who, here? And even when the live dancers - one male, three female - start moving around with the two life-size dummies, it's still not always clear who is initiating the moves. Do the dancers have to take certain steps because the other body is inanimate? Or do the steps exist regardless and simply act as shock-waves on the stuffed dolls? What's never in any doubt, however, is the way in which Colette Sadler weaves chewy strands of metaphysical debate into the physicality of her choreography. And this newest work, a Tramway co-commission that continues the venue's supportive rapport with Sadler, sees her exploring a fascinating lexicon of gestures, stances, travelling steps and body language that doesn't assume the everyday mobility and moving parts of the human body.

Her young company - Eva Baumann, Jara Serrano Gonzalez, Sybille Muller and Maxwell McCarthy - throw themselves wholeheartedly into Sadler's process of deconstructing and rearranging movements. At times, it's as if they've managed to dis- locate their limbs from the sockets in order to mimic the gawky, splayed angles of arm, leg, fingers and feet that come easily to the dummies. They slump and flop, as if boneless. And then they strap on a variety of prosthetic limbs - an extra leg, maybe, or perhaps an arm - to parade a surreal assortment of hybrid creatures with a penchant for untoward acrobatics. And this - like the subsequent phase that sees two huge cardboard rectangles animated by unseen dancers - is goofy and funny in a cartoon way but at the same time it's oddly unsettling. The extra limbs, incorporated into the everyday clothes, and the facelessness of the cardboard (which, curiously, seems to take on distinct personalities) totally disrupt commonplace notions of what dance is, or indeed why we assign aesthetic values, and preferences, to different types of movement. A brilliant provocation, underpinned by disruptions from a Zoviet*France soundscore.