After London can be seen as an early example of post-apocalyptic fiction: after some sudden and unspecified catastrophe has depopulated England, the countryside reverts to nature, and the few survivors to a quasi-medieval way of life. The audiobook has two parts. The first, The Relapse into Barbarism, is the account by some later historian of the fall of civilisation and its consequences, with a loving description of nature reclaiming England: fields becoming overrun by forest, domesticated animals running wild, roads and towns becoming overgrown, the hated London reverting to lake and poisonous swampland.

The second part, Wild England, is largely a straightforward adventure set many years later in the wild landscape and society (here too Jefferies was setting an example for the genre); but the opening section, despite some improbabilities, has been much admired for its rigour and compelling narrative.

John Richard Jefferies (6 November 1848 – 14 August 1887) was an English nature writer, noted for his depiction of English rural life in essays, books of natural history, and novels. His childhood on a small Wiltshire farm had a great influence on him and provides the background to all his major works of fiction. For all that, these show a remarkable diversity, including Bevis (1882), a classic children's book, and After London (1885), an early work of science fiction.