Plague rages through London, but Nick Knight and LaCroix are immune to its effects. The same cannot be said for Gerald Archer, a courageous doctor who insists on braving the danger in order to treat his patients. He defies a local preacher, who insists that they would not be ill had they not in some way offended God. Nick is struck by Dr. Archer's devotion to his profession, and suggests to LaCroix that he be brought over so that he be spared the risk of being infected by one of his patients.
LaCroix is agreeable, Archer is approached and intrigued, and Nick turns him into a vampire. Shortly thereafter, though, he and LaCroix are surprised to learn that the preacher is accusing the doctor of somehow increasing the mortality rate among his patients. When they confront him, Archer admits that he is now preying on them instead of treating their disease. Becoming a vampire has radically altered his perspective of mortality. Nick is horrified.
The preacher and his followers attack Archer, who does not realize that they pose any danger to him. Yet, like any vampire, he must recoil from the cross held by the preacher. A torch sets his clothes alight, and he is burned to death.
At the back of the crowd, Nick and LaCroix quietly and prudently slip away.