In some unspecified period in the near future the water levels around the world have risen catastrophically. All beaches have disappeared and the UK is “protected” by the Wall, which has been built around the entire coastline. It has been designed not just to keep the sea out but also the “Others”, desperate people seeking to gain entry into the country. A form of national service is in place with Defenders (drawn from the young and fit) tasked with manning the Wall for two-year stints. We follow Kavanagh as he undertakes his first day on the Wall, the skull-crushing boredom of staring out to sea only punctured by the thought of attack from the Others. The novel is an obvious flashing warning light on everything from eco concerns to a pull-up the-drawbridge Brexit, but the author doesn’t forget to include a gripping story and a hierarchical society every bit as well drawn as Margaret Atwood’s in ‘The Handmaid’s Tale’. The latter sections also reminded me Robert C. O’Brien’s post-apocalyptic ‘Z for Zachariah’ and ‘The Wall’, like O’Brien’s 1970s young adult classic, is perfect for study (both in schools and within the current cabinet).