The graffiti on the grey concrete walls of the disused prison in Turku are like cave paintings from a lost civilisation in the Finnish artist Saara Ekström’s ‘Shadow Codex’, which, with a simple but overwhelmingly suggestive approach, lets text, drawings and the shabby pinup posters speak their own language about incarceration and institutionalised punishment. Each cell is a gallery, an indexical imprint of the anonymous inmates’ minds, from a past conjured forth by the film’s timeless black and white 16mm images, with a gloomy melancholy that borders on madness. But, at the same time, the surveillance machinery, the architecture and the many layers of engravings tell us about a society which, in its attempt to maintain law and order, creates monuments of its own shadow – set against John Cage’s ‘Perilous Night’.