Throughout history marking the home has often been used to convey urgent information about the ‘health’ of its inhabitants. These strategies frequently target the door or entrance to the household, as it presents a porous boundary between public and private spheres. This chapter engages with several historical examples that examine how the door has been marked during periods of ‘death’ and ‘disease’ in order to prevent further spread of contagion. Specifically, it explores the use of the Plague Cross during the Great Plague of London in 1665, which became a means to regulate the movement of the infected. This is compared with modern-day forms of inscribing the door and how ‘Plague Markings’ have re-emerged in the wake of the COVID-19 pandemic. The discussion considers that while these forms of inscription often serve valuable public health functions, they are also embroiled in a distinct politics of regulation. In many cases, marking sites of ‘contamination’ facilitates the categorisation of the ‘Other’ which defines who and what is able to enter society. Inscribing the door thus becomes an act of ‘the powerful’, signalling who is able to exert control over the body and the threshold.