A line is a curious thing. It links two points, or it divides two sides: you can have a line of communication or a line in the sand. In 'The Russian Linesman: Frontiers, Borders and Thresholds', the new show at the Hayward Gallery curated by Turner-winner Mark Wallinger, we see both sides, as it were.
The titular linesman is the official who helped England to its 1966 World Cup win by deciding that the ball had crossed the line. This is the least interesting thing about the show: there is far more inside that this might suggest.
Wallinger's own contribution to the show is a gigantic mirrored Tardis, which straddles the line of existence: it is clearly there, but its mirrors reflect the room (and us), so that there is no hint of anything solid, only images. As the picture makes clear, at certain times it even seems transparent, rather than reflective. It is a neat trick.
One of the key pieces, which has more than art-theoretical resonance, is Bertelli's Continuous Profile of Mussolini (1933). The dictator's profile has been shaped by carving contours all the way around a ceramic centre: whichever angle the sculpture is viewed at, there are always two faces of Mussolini. (It draws on the two-faced head of Janus, god of doors and the origin of 'January', adjacent to it.)
As well as being artistically innovative, the work is a politically subversive statement: Mussolini is watching at all times, but he has no solidity, no definition. He is and he isn't . Given that this is an official bust, one must be surprised by his tolerance (or lack of understanding).
Thomas Demand's Poll (2001) is a curious experiment too: a cardboard recreation of a photo taken during the election recount of 2000, then photographed. This is the line between the government America had and the one it lost, but also the line between several kinds of reality: the real scene, the photo of the scene, the carboard recreation of the photo of the scene, the photo of the cardboard recreation of the photo of the scene. A veritable fractal, or two mirrors casting images at each other.
There is a lot more than this, and each piece is its own complex variation on the idea of lines, which saves the show: rather than being simple demonstrations of the use and abuse of liminality, we see that there are far more than two sides to a line.