During the 2019–2020 Hong Kong protests, after 6 months of ongoing actions, and with protesters facing escalating stakes from police shootings and other violent repression, students began to fortify a number of the city’s major universities and occupy vital roads nearby. This lead to a peak moment in the protest movement—the siege of the Hong Kong Polytechnic University. Protesters gathered at the university to defend their roadblocks, while the police shot tear gas and used water cannons to shower the protesters with water containing blue colouring and chemical irritants. 1,458 canisters of tear gas were fired at protesters, as well as 1,391 rubber bullets, 325 bean bag rounds, and 256 sponge grenades. The city’s hospitals were overwhelmed by the number of protesters needing urgent medical attention. Burn with Us documents a first-hand view of the conflict, and its results, in a fly-on-the-wall style.