A slow radio journey into illumination, drawing inspiration from light beacons and signal fires. Used across the centuries as alert systems and warnings of invasion, but also for celebrations and as emblems of hope, this programme lights up the darkness, conjuring a chain of signal fires and beacons out of sound and reflecting on their meaning and purpose. Drawing on short quotes from literature from Ancient Greece to the present day, we move from the lighting of a match, to the creation of a chain of beacons, and end next to the coast at a lighthouse casting its warning light out over the sea. Producer: Catherine Robinson for BBC Wales