A staple of the Radio 4 panel show I’m Sorry, I Haven’t A Clue, the game “One Song To The Tune Of Another” is about finding humour in incongruous combinations of lyric and melody: the Undertones’ “Teenage Kicks” to the tune of “Jerusalem”, or Pink’s “Get The Party Started” to the tune of “A Policeman’s Lot Is Not A Happy One”. A similar kind of incongruity is at work in David Firth’s long-running animation series Salad Fingers, which derives much of its unsettling fascination from the transmutation of the wholesome into the unwholesome. Hospitality, kinship, ritual, intimacy and memory are fractured and reconstituted, turned into the playthings of a guileless gremlin who delights in a sort of solipsistic travesty. But if Salad Fingers were solely about profanation, it would not have such an eerie effect. What really gives Firth’s animation its kick is the way that its titular protagonist, who mishandles everything with his misshapen digits, reveals the latent sadism and corruption within the wholesome itself.

The title “Salad Fingers” comes from a conversation between Firth and a friend, who was mocking his dexterity as a guitar player. Salad fingers are fingers ill-suited to skilled work, fingers which botch everything they come into contact with. From the first episode, however, it’s clear that these appendages are also erogenous zones: Salad Fingers loves to stroke unclean, abrasive objects such as rusty spoons, to be stung by nettles and pierced by spikes. He is a creature of masochistic enjoyment, especially focused on the tactile surface of the skin.

This sensuous passivity is combined with a powerful will to control, in fantasy, the parameters of the scene: Salad Fingers is forever issuing instructions and corrections, rebuking the objects of his fantasy for minor deviations, and playing out scenarios of correction and punishment. His relationship to the world is similar to that of a schoolchild recreating, in play, the authoritarian disciplinary environment to which he is subject, while seeking opportunities for libidinal release within that environment. He is a kind of helpless tyrant, reacting in an improvisatory way to incomprehensible and horrifying events and refiguring them as occasions both for setting things to rights, and for a kind of furtive satisfaction.

The philosopher and writer Hélène Cixous once wrote: “what is reading? It’s eating on the sly”. Salad Fingers is in this sense a reader, a roving interpreter of a desolate environment which seems to lack all object permanence, or any sense of being “built up” in the way that human social environments typically are. His world has been described as “post-apocalyptic”, but I prefer to see it as a kind of dream-image of our own world, in which significant fragments appear against an inchoate background, much like the world of Catherine Storr’s Marianne Dreams (filmed as Paperhouse). Salad Fingers’s own appearance is a little like a childish drawing of a human being, although the decaying stumps of teeth in his mouth connect him to animality and mortality, to appetite and decay.

What are the constituents of the “wholesome” in Salad Fingers’s world? They are almost all organised around cultural references to the Britain of the period between the First World War and the end of the 1950s, the nostalgic topos of a familiar Conservative repudiation of the 1960s with its supposed slackening of discipline and desecration of sacred values. The finger puppets who stand in as Salad Fingers’s family are given names such as “Hubert Cumberdale” (all the more amusing since the ascendency of Benedict Cumberbatch as a well-known figure of risible poshness) and “Jeremy Fisher” (originally the name of the frog in Beatrix Potter’s stories for children). Salad Fingers has a radio rather than a television, on which he listens for news of the “Great War”. He himself speaks in a slightly formal, euphemistic English, like a nanny or a schoolteacher talking to children. These reference points are meant to be consoling and reassuring, but in fact carry considerable menace: at any moment the finger puppets or the radio may emit a squall of angry fuzz, an expression of annihilating hostility. This is the experience of a child faced with adult anger they are unable to understand or process, an anger that erupts unpredictably from behind the surface of decorum and proper manners.

The most recent episode of Salad Fingers introduces a literal parental figure, a domineering and foul-mouthed “glass mother” who screams at Salad Fingers from behind the mirror, demanding service and obedience and threatening to burst out of the mirror to snatch and engulf him. I found this a bit on the nose, but the episode was satisfying nevertheless for the way Salad Fingers dealt with the incursion of this figure into his private world. A “glass brother” Salad Fingers — obedient and good, and clearly in league with the mother — also appeared in the mirror-world, representing the “golden child” who is accepted and validated, but also plainly a bit of a sneak (in place of Salad Fingers’s teeth, he has terrifying pointed drills). The episode revolves around Salad Fingers’s creation of an enhanced Hubert Cumberdale finger puppet, clad in scraps of human flesh, and capable of independent life and movement: a love-object which Salad Fingers clearly finds beautiful, although it is oozingly repulsive to the viewer. Salad Fingers is now in the position of a parent with respect to his creation, which clearly embodies his own hopes for life, admiration and enjoyment: the meat-puppet declares “I just want to dance on the rooftops for all to see. I’m a big boy now”.

When the scum mother and glass brother kidnap this puppet, Salad Fingers must journey through a portal to the mirror world to rescue it. On his return, he shatters the mirror from which the Glass Mother screams obscenities at him, grinding it into dust. He then mops up the glass dust using the sticky flesh of the meat puppet Hubert Cumberdale, and licks it off the puppet’s head with evident satisfaction, returning to his primal masochistic pleasure in tactile abrasion. His final act is to gather up a remaining shard of glass, pierce a finger with it, smear it with blood and then seal it in a box. Much like the ending of The Babadook, this suggests a negotiation with trauma: Salad Fingers cannot entirely destroy the image of the mother, or relinquish his attachment to it, but he can interiorise it on his own terms, coating it with his own vital fluids and locking it away.

To my mind this episode has a feeling of finality about it, since its explicit treatment of parent/child relationships places a kind of interpretative lock on the preceding episodes. But it would not surprise me to see a subsequent episode redefine the terms of Salad Fingers’s dream world, or introduce some new disturbance into its framing. Salad Fingers’s dream-work confronts, in miniature, both the intimate terrors of childhood and the wilful amnesia of Brexit Britain, which endlessly consoles itself with an image of decency and propriety that it once briefly recognised as the hypocritical disguise of brutal inequality and violence. Of this work, there is plenty more to be done.