Matthew Holness' cast-iron commitment to never breaking character as his self-aggrandising horror novelist Garth Marenghi, not in interviews, nor the Q&A session with which he 'pads' this latest book tour, remains seriously impressive. The Perrier Award-winning creation has acquired a rich, ridiculous mythology since emerging at the Edinburgh Fringe a quarter of a century ago. And naturally, a narcissistic hack like the self-styled 'dream weaver' wouldn't deign to share his stage with a support act. Nevertheless, through a combination of 'the titan of terror's' projection of unshakeable belief in his own abilities; a hark back through the annals of Marenghi lore to his association with folk singer Merriman Weir and some sketchily occult shenanigans, he opens the show possessed by some electric guitar axesmithery that he's mastered since picking up the instrument a week ago. What follows is a prog-rock portrayal of war between angels and demons, the tongue-twisting grandiloquence of their Latin nomenclature so daftly convoluted yet so po-facedly shared that it's worth hearing the lyrics twice.

This Bursted Earth, the supposed final part of the inexhaustible pulp poetaster's TerrorTome trilogy, and itself a collection of three 'mini tomes' is more of a mixed bag, though it's dense with prose so tortuous that it's never less than compelling. Marenghi sells the passages he reads with absolute conviction in his own genius. And the wheeze that his thinly disguised alter-ego Nick Steen, horror author-turned-demon slayer, is persecuted by the monsters of his own imagination-turned-flesh is a boon, unwittingly testimony to so many of Marenghi's own faults and insecurities.

The highlight is the concluding tale, ‘SpeciMen’, a hilarious confluence of haemorrhoids, alien abduction, snooker legend John Virgo and Steen/Marenghi's relationship with his own virility. In Bonelord, Steen casually gaslighting his female sidekick while agonising over betraying the male villain is archly presented too.

Garth Marenghi: This Bursted Earth will tour the UK until May 2026; reviewed at Queen's Hall, Edinburgh, Saturday 1 November.