The Tube is a paradoxical and apt site for negotiating the rising social and economic inequality which has been observed in London in recent years: Its lines can be seen as the gradient which connects many different social strata, while also disconnecting some. After a short sketch of the impressive array of cultural production about the Tube, which is as often celebratory as it is critical, we discuss four books from the 2013 Penguin Underground Lines series, which was published on the occasion of the Tube’s 150th anniversary. Each of the slim volumes was inspired by a different Underground line. The books’ different points of view and different writing styles add up to a composite portrait; none is ‘simply’ social-realist. All of these texts speak about social inequality in ways that can surprise readers aesthetically as well as by (re)presenting a London that might be hidden from them and normally go unnoticed.