Chapter 3 looks at the port city of London, where the Plague of Provence caused waves of fear, opposition, and intellectual inquiry. Taking place against the backdrop of the recent South Sea Bubble, the epidemic became a major topic of discussion among politicians, journalists, scholars, physicians, grocers, and merchants as they protested perceived infringements on their civil liberties, or debated the nature of contagion and the usefulness of quarantine. In 1720, just as plague cases emerged in the south of France, the bursting of the South Sea Bubble unleashed a wave of anxiety and suspicion. Passionate attacks against the perceived injustices of the Crown as it attempted to enact quarantines and impede illicit commerce were filled with accusations that government authorities and “South Sea scheme men” meant to take away the inviolable rights of the people under the pretext of a foreign plague. Meanwhile, debates between contagionists and anti-contagionists about the transmission of infectious disease also erupted with special force in the wake of the 1720 plague. This chapter explores these reactions within the larger historical context of early-eighteenth-century politics and diplomacy and considers the various factors that came into play as England designed its new public health policy.