At the end of the novel, Neville finally sees things from his enemies’ point of view. Throughout the novel, he’s operated under the assumption that humans are “right” and vampires are “wrong”—and, therefore, that he’s morally justified in killing vampires in their sleep. However, as he ingests the pills (which will, presumably, cause his death—the “final lethargy”), Neville realizes that he’s no better than the vampires he’s been fighting. Indeed, Neville is just as much of a murderous monster as vampires once were in human society: like a vampire, he sneaks into people’s houses and kills his victims in their sleep. Thus, in the final line of the book (which also serves as the book’s title), Neville accepts that he is a monster. Furthermore, the final line suggests that human society—of which Neville was the last representative—is now fading into the past; it, too, has become a mere legend.