Luis Guerra’s FOG is, I think, about screens and endurance. Four very accomplished dancers appear in a cube of light behind a translucent scrim, as if inside a goggle box. Facing us, they move like matchstick figures, sideways only, limbs flicking stiffly in stop-motion animation sequences that look as scripted by computer code. They move very fast, and it takes a long time for nothing more to happen. It’s like watching a screen saver. After a long blackout, three faintly menacing phantasms appear, one red, one green, one blue – the primary colours of screen light. With imperceptible slowness, green points an accusing finger at red, then at blue. Blue points to red. Now, a long whiteout. The dancers lift the screen and come forward – slowly – with supplicating jester’s gestures. The piece balances on the cusp between trance and tedium, its means as clear as its meanings are foggy.