As COVID-19-related closures affected theatre and performance venues worldwide, the question of how theatrical practices might be adapted to these new circumstances became particularly pertinent in the context of immersive theatre and site-specific performance, forms which heavily draw on the audience’s experiential encounter with site and performers for its process of meaning-making. Focussing on ANU Productions’ The Party to End All Parties (2020) as a hybrid form of site-specific pandemic theatre set in the cityscape of Dublin, this article investigates how the production translated the “host/ghost” relationship as a central aspect of site-specific theatre to the virtual realm. It demonstrates how this notion is transformed into a thematic thread woven into the performance, arguing that it engages with the host/ghost relationship through spatial as well as temporal “ghosting,” which blurs the lines between the contemporary setting of lockdown Dublin and the historical landmark of O’Connell Bridge as a site inextricably connected to the emergence of Ireland as a republic. At the same time, this notion is explored through the connections between presence and absence, visibility and invisibility (or, indeed, spectrality) in the three characters’ personal journeys.