Despite Francis Lawrence’s I am Legend being a box office success, it fails in countless ways living up to its source material. I want to go through both novel and film, examining their differences while discussing how the film falls short in being a proper adaptation.
The most obvious issue that the film has is the portrayal of the creatures as mutant zombies in contrast to the book’s depiction of vampires. The reason this is an issue is because the book spends a large amount of time talking about vampire folklore and how Robert Neville applies this knowledge to the real world. The point of all of this is for questions to be raised such as: Why does garlic repel vampires? Why can’t they look at crosses? Why are they only killed by wooden stakes? Why do they die when exposed to sunlight? And each of these gets explored and answered by Robert as he continues his research. Vampires are the driving force of the novel and shows how one man continues surviving in this apocalypse despite the odds being against him. But the film on the other hand takes everything that the novel has to say and throws it out the window so that they can instead focus on mutants (which go by the name Darkseekers). Now I could accept this change if the film had as much exploration and story that the novel did when it comes to the vampires, but they don’t, it barely has anything to say about them. The most that we understand is that when administering vaccines to people for cancer, there was a virus outbreak, which caused the population to turn into Darkseekers. Aside from their origin, little else is revealed about them and there is virtually nothing explained with regards to Robert’s cure for them in the film. The only thing Darkseekers and vampires have in common is that they are weak and scared of the sunlight. Both novel and film portray the creatures as very primal and aggressive, but the film never evolves beyond that, they never change, they never adapt. However, in the novel, it’s a much different story since the vampires were very primal at the beginning, but later due to mutation, evolved into two species. The one species acting like animals while the other evolved more like humans, being able to walk and talk, go out in sunlight, and basically got past all of their primal weaknesses. They are the new dominant species of the world and have emotions and families just like humans before them did. There is seemingly no difference between Robert and the new vampires except for perspective. Perspective is almost the entire point of the latter half of the book, but the film doesn’t show this quite as well. The film shows us Robert surviving and killing Darkseekers as a means of protection and that’s all it ever shows. Except for the alternate ending which we will discuss next.
The endings of both mediums are drastically different from one another, and it’s a shame that the film took the route that it did. The film ending that most people are familiar with since it was the theatrical cut, ends with Robert saving Anna and Ethan by leaving them with the cure as he sacrifices himself with a grenade killing Darkseekers all around him. After that Anna and Ethan arrive at a survivor’s camp with the cure and explains how the Legend of Robert Neville was created by his sacrifice. This is a very optimistic ending, and it makes sense considering its blockbuster status, as big films want to have the audience leaving the theater with a happy ending. Conversely, the book has a much more cynical view, in which Robert is taken prisoner by the vampires and is scheduled for execution due to his ramped killing of vampires. He was ignorant of the differences between the two types of vampires, as previously discussed, and viewed them as all the same. But as he’s standing in his prison cell, he looks out onto a sea of vampires waiting for his execution and it becomes clear to him. All this time he’s been reading and studying on the Legend of the Vampire, which humans once feared, but the tables have turned, leaving Robert to become the legend who's been preying on and killing the new species of the world. They look at him the same way he looks at them, a ruthless monster. But looking at the film's alternate ending it's clear that this gets much closer to the novel’s intentions. It has the Darkseekers taking back the woman Robert kidnapped and shows them with more emotions. Where they weren’t after Robert in the first place, they just wanted to get back one of their kind from the guy who's been killing them. And this shows the same perspective as the novel does by having you decide who the real monster is.
In the novel, Robert is depicted as alone and takes the opportunity to perform more of a character study on him. Unlike in the film, Robert is not trying to be a hero but rather survive and understand the world around him. The film changes many of Robert's characteristics and places him in more situations where he has to look out for others instead of himself. Much of the film is dedicated to him saving his dog or Anna and Ethan, who are not even in the novel. The film largely ignores Robert’s struggle with alcoholism and living in isolation, which are some of the best moments in the novel.
I don’t think this movie is a proper adaptation and it’s unfortunate since it has such a rich source material to take from, but this movie does stand on its own despite all of its flaws. I can understand why it was such a successful movie and why the general public enjoys it. It is a decent post-apocalyptic film that caters to its audience and changes things to get a more emotional response. Unfortunately, when adapting a book, there will always be differences and a lack of detail as it is difficult to portray everything in a book on the big screen. In the case of I Am Legend, it ditches the charm and grit of the book in an attempt to appeal to a mass audience, which gives it a watered-down and lackluster experience in comparison.