Fear of the return of "King" cholera joins Whitechapel's H Division and the independent City of London police forces amid the panic. Captain Jackson's autopsy discounts cholera and indicates St Anthony's Fire caused by wilful contamination of food in both boroughs. Inspector Sydney Ressler (Patrick Baladi) joins Reid’s team as they scour Whitechapel for clues and connections of five dead City of London workers that include transvestism and homosexuality. Reid's wife seeks patronage for her charity efforts and is rebuffed and succumbs to the same illness seeing her dead daughter in her delirium. As Jackson’s lab fills with bodies, and with no clear connection between the victims to be found, the team work against the clock to find some underlying pattern amidst the rising tide of sickness and death.