Alternative Endings

The original film revealed the fact that Neville was actually a villainous character at the end, which caused a lot of dissatisfaction among the audience at the time of the screening, thus the director decided to shoot an alternative ending completely contrary to the novel's ending.

Official Ending Summary:

The final version of the film ended as: Neville finally discovered the cure for the Darkseekers, they stormed into Neville’s house and blocked Neville and the other two survivors inside a room with solid glass. Neville eventually chose to sacrifice himself and died along with the leader and some of the other Darkseekers. The two remaining survivors arrived at Vermont free of infection with the cure for the virus Neville had researched. This ending means that eventually all the infected mutants will be cured and the world will return to the way it was before the outbreak.

Alternative Ending Summary:

According to director Francis Lawrence, the alternate ending was supposed to be the official ending, which with a more emotional climax at the end, and is designed specifically for the film. In the original ending when the Darkseekers stormed into Neville’s house and were locked behind a solid glass, the leader of the Darkseekers drew a butterfly shape on the glass with blood, Neville realized the connection between the female Darkseekers he has been doing the experiment on and the butterfly. He returned the healed female Darkseekers to the leader of the Darkseekers. Unfortunately, Neville discovers that the so-called vampiric mutants are actually highly intelligent species still with human emotions, and they are not interested in the cure Neville has developed. Eventually, Neville realizes that he is in fact the terrible monster to the Darkseekers. The cure he has been insisting on developing has not saved all of humanity.

Monster VS. Hero

The new version of the ending completely ignores the fact that Darkseekers may have human emotions, including many evidence shown in the previous part of the movie already foreshowing this fact:

Darkseekers know taming dogs to use for fight
They have a clear hierarchy concept, they have a leader.
The leader of the Darkseekers used the same method as his lover was captured to set up Neville
The Darkseekers followed Neville in the shadows after the capture of the Darkseekers leader’s daughter.
The Darkseekers attacked Neville in waves instead of all at the same time as they knew that the house was surrounded by ambushes.

Whether or not Neville realizes at the end of the film that the Darkseeker actually has human emotions is decisive for the meaning of the film as a whole.

The new ending turns the film into a generic personal heroism movie where simply one person saves the world. While this ending maintains the fact that Neville commits suicide as so in the novel, however, it is the exact opposite of his original reason for doing so, as he goes from being the monster to the world's hero.

Neville appeared as the last hope of mankind since the beginning of the film, so the audience considers him as a savior. The casting of such characters is crucial, the film finally decided to have will smith, a very American iconic actor. Plus the setting in New York City, both factors are very representative of American, which will make people believe more in the reality of the fictional world presented in the film. They "signifying power transcends both the single film and the boundaries between fictive screen-worlds and 'the real thing '" (Hutcheon 251). Neville represents not just a fictional character in the film, but a hero who represents an entire country or even the entire mankind.

The whole film is filled with the theme of hope, and even the virus initially appeared as a hope to cure cancer, so the original ending makes Neville a monster is not acceptable to the audience. The fact that Neville is the last hope of mankind destined for his death has to be a worthy one, which needs to be beneficial to save all of humanity.