With the recent relative success of the third attempt at making a big screen adaptation of the novel, some might find now to be an appropriate time to discuss the merits of Richard Matheson's apocalyptic science fiction classic, ?I Am Legend.? The main vehicle of the story, which has remained virtually consistent throughout all the adaptations, is a strain of bacteria that combines two dangerous traits. The first is an antibiotic resistance so potent that no antimicrobial drug or bacteriophage could be used to effectively counter it. The second would be the notable effects it has on those who have become infected, as well as how the ones who died of the infection continue to ?live.? Humans killed by the infection begin exhibiting traits associated with mythical vampires, such as an aversion to sunlight and garlic.

The bacterial agent is not fully explained in the novel itself, which prefers to delve into the lead character, Robert Neville, and his research into the effects of the plague. Like most book-to-movie adaptations, ?I Am Legend? suffers in the translation from literary form to on-screen action. The movie adaptations of the original novel, Charlton Heston's ?The Omega Man,? Vincent Price's ?The Last Man On Earth,? and Will Smith's ?I Am Legend,? all eliminate the duality of the infected survivors. Whereas the infected are not divided in the movies, the novel shows that there are two groups of infected. The first are vicious, vampire-like killers that consist primarily of the dead that have become reanimated by the bacteria. The second are the still-living infected, who Neville takes pains to kill along with the already dead.

The incredible antibiotic resistance of the pathogen is shown by the novel to have made it nearly absolute in wiping out the human population. The only signs the novel shows of hope for the human race are Robert Neville, the only human to show signs of immunity to the infection, and a colony of infected humans who claimed to have found a way to ward off the infection's effects. It is noted by some that, while the infected to manage to maintain some semblance of civilization in their colonies, it is portrayed by the novel to collectively show signs of psychopathy. The novel does not discuss how the infection's effects are being countered, but the relative absence of advanced laboratories and the bacteria's antibiotic resistance may mean that the treatment is herbal in nature.

One final detail about the translations from novel to movie would be the final resolution. In all the adaptations of the movie, Neville is granted hope from his despair and loneliness by finding some sort of cure for the bacteria's effects, generally by extracting an antidote form his own immune blood. In the novel, there is no such hope given. Neville is captured by the still-infected, who have come to see him as a nightmarish monster, and publicly execute him. The title of the novel is explained during Neville's final thoughts, wherein he realizes the rather ironic nature of the new society's perception of him. In the same way that vampires are a legend to modern humans, Neville had become a legend to the infected people he so ruthlessly killed in their sleep.