The tension between specialised and commonsensical notions of microbes in the last decades of the nineteenth century resulted in ‘ bacillophobia'; a marked anxiety amongst the public concerning the threat posed to the individual by germs. This article investigates how the conceptual impact of bacillophobia challenged the cohesion of late Victorian society. It focuses on the role played by bacteria in the negotiation between interiority and exteriority in three novels, all published in 1897: Bram Stoker's Dracula, H.G. Wells' The War of the Worlds and Joseph Conrad's The Nigger of the “Narcissus”. The analyses of the works emphasise the varying functions of bacteria in them – as allegory in Dracula, as plot device in The War of the Worlds, and as theme in The Nigger of the “Narcissus” – and the varying degrees of ambiguity they are represented with. Bacteriology participated in what the German sociologist Max Weber referred to as the ‘ disenchantment' of the world, which is characteristic of modernity, but the three works all testify to a re-enchanted fear of the possibility that nature might not, after all, be controllable.