Isabella Martin’s series of short videos was filmed in four disparate locations (Denmark, Germany, Britain and the Netherlands) along the edge of the North Sea. Taking place in different weathers (and different sea conditions), they share an identical frame – with Martin standing facing the shore, and the waves breaking behind her and around her. Stoic, unmoving, a human breakwater amidst the sea-swell, she eventually starts to signal towards us in the language of semaphore: rotating through an alphabet of signs that most of us now lack the knowledge to comprehend. On a coast where wind turbines gyrate in unison as soon as the sea breeze stiffens. Martin’s upraised, gesticulating arms appear to be raising an alarm – conceivably, with water flooding up to her torso, about the threat of rising tides. Is this the message she is trying to relay? Is she waving or drowning? Back on dry land, we can be fairly sure we are being issued a warning about a sea change that is about to happen, but we do not know quite how to interpret it, or how to proceed.