This experimental paper presents a chronicle of paranoid reflections, inscrutable nightmares and alienated psychogeographical wanderings amongst the interstitial spaces of an abruptly shutdown city. Welling up through this murky stream of consciousness, an image gradually emerges of the peculiar socioecology of the COVID-19 pandemic, in which capital and virus, animal and human, dream and reality, biopolitical management and governmental farce, become entangled in ever more surreal and disconcerting configurations. The narrative is framed by the targeting of the UK population as the future subjects of a putative herd immunity, which was initially posited by the government as the objective of its epidemiological strategy. The concept of herd immunity is deployed as a metaphor for the ideological closure of the political possibilities fleetingly opened by the crisis. Glimpses of the opportunity created by the lockdown for a radical break with the status quo are replaced by a realisation that this unique chance is being missed. Amidst a barrage of news reports, a plague of fever dreams and a litany of bewildering encounters with the rapidly mutating social and material fabric of the city, a terrible suspicion grows: an eventless future is coming into existence, and it will be inhabited by the Immune Herd.