There is much to admire about A Feral World, a low-budget post-apocalypse drama from first time feature writer-director David Liban, most notably the fact that – like Richard Linklater’s Boyhood – it was shot sequentially, over the period of a few years, with the actors ageing with their characters. This is especially notable as the film’s co-protagonist, Sonny (played by Liban’s son Caleb), begins the story as an eleven-year old, growing into an awkward teen by the story’s end. Sonny is alone in a scarred landscape as the story begins, the result of an attack by a mysterious Entity using nanobytes, and soon encounters Emma, a mother looking for her own missing child.

Danielle Prall, with half a dozen years under her belt in low-budget movies, carries the film with a hope infected with weary sadness, taking Sonny under her wing and giving him a purpose in a world without one. Emma’s search for her daughter brings the pair into conflict with child-gathering warlord Jasper, who may know something about what brought the world to where it is, and Timothy McCracken plays him as the best kind of villain, one who thinks what he is doing is right.

A Feral World is hampered by some ropey special effects, belying its tiny budget, and also some issues of agency, but is a worthwhile entry into the growing catalogue of movies which may turn out to be more survival guide than warning as the years progress. If you like spending time in an all-but deserted world, it’s an hour and three-quarters well spent, and you’d hope this isn’t the last we see of the director or his cast.