For two decades the international mail system fostered a network of underground artists, exchanging cassette tapes of music and homemade artwork - all under the radar of main stream media. We track down some key figures in the cassette scene, and follow the web of connections outward from the UK around the world, mapping the impacts and their ongoing effects. We speak with musicians, label runners, and fanzine writers, who share their experiences of connecting through the mail system and its ongoing effects on their lives.