John Lanchester’s speculative, dystopian cli-fi novel The Wall (2019) is set in a near-future Britain, where rising sea levels have led to a wall being built around the entire island. The wall is manned by Defenders to prevent those living outside the wall, the Others, from coming in. Britain of the novel has been transformed into a walled state within a climate changed Earth. Life inside the wall has been relatively little-affected by climate change, and the standard of living is somewhat similar to contemporary Britain. Beyond the wall remains largely unknown for much of the novel, since its focalisation on the protagonist Joseph Kavanagh means that as a reader we know as much as he knows: climate change has dramatically transformed whole parts of the planet and thus turned millions of people into climate refugees. Drawing on Adeline Johns-Putra’s engagement with intergenerational ethics in the context of climate change and the contemporary novel, this paper will analyse the generational elements of The Wall, in particular Kavanagh’s perspective from a near future, climate-changed earth, looking back (in anger). The paper will then make a comparative analysis between this fictional, future generation point-of-view and examples from contemporary speeches, documentary films and popular science publications, which have employed (no doubt genuinely) an imagined future generations trope, evidently designed to raise a sense of anxiety and alarm that leads to action on curbing global warming. James Hansen, Barack Obama, Al Gore, Leonardo DiCaprio and Greta Thunberg represent some of the key scientific, political and celebrity voices whose imaginative future scenarios are in many ways (fictionally) corroborated in Lanchester’s novel. This paper argues that the novel and recent climate-change discourse that employs the children-and-climate-change trope sets up a generational division (old-young, present-future) that may ultimately risk obscuring societal attitudes to climate change.