How did I Am Legend end in the book?

Francis Lawrence's 2007 film I Am Legend had not one but two endings, and while both are different from what happens in the original novel by Richard Matheson, the alternate ending not shown in theaters is a lot closer. The movie stars Will Smith as virologist Robert Neville, the apparent sole uninfected survivor in a post-apocalyptic version of New York City where most people are dead, and the remainder have been transformed into monsters that hunt at night.

In the original ending for I Am Legend, Robert is cornered in his basement laboratory along with fellow survivors Anna (Alice Braga) and Ethan (Charlie Tahan), with the hemocytes having broken into the house. When the leader makes the symbol of a butterfly on the reinforced glass, Robert connects it to the butterfly tattoo on the female hemocyte he's been experimenting on. He realizes that the leader only wants the return of his mate, and that the hemocytes - whom Robert believed incapable of higher brain function - can experience attachment, love, and even restrain themselves from committing violence. Looking at the wall of photographs of his past experiment subjects, Robert understands that he is the monster in the eyes of the hemocytes: a predator who has been capturing and torturing them.

The ending did not go down well with test audiences, who were unhappy with the implication that the hero of the movie was actually a villainous figure. It was replaced in I Am Legend's theatrical cut with a more traditional Hollywood ending, where the hemocytes remain mindless savage zombies and Robert dies a hero after discovering a cure for the virus. The original ending, however, is much more in line with what happens in the I Am Legend novel. In fact, without the original ending, the movie's title of I Am Legend doesn't actually make much sense. In the book, "I am legend" are the final words that Robert thinks on his deathbed, as he realizes that in death he will become a terrifying legend just like vampires once were.

Yes, in the book version of I Am Legend the hemocytes are explicitly labelled vampires and come packaged with many vampiric traits, including not only a deathly aversion to light but also a fear of garlic and religious iconography. They are also, besides their pale skin, very difficult to distinguish from regular humans. They retain all their intelligence and can still talk, coming out at night to taunt Robert outside his house and tempt him to leave. As in the movie version of I Am Legend, there's a pivotal moment in the book where Robert meets a woman who appears to be another human survivor, Ruth. Her ability to walk around in the sun seems like clear-cut evidence that she's not a vampire, but he becomes suspicious of her aversion to garlic and her unconvincing story about how she's survived all this time.

Sure enough, it's revealed that Ruth is actually a vampire and was sent to spy on Robert after he killed her husband. She reveals that some of the vampires do not die and return as undead monsters, but have discovered a pill that controls their bloodlust and prevents the infection from killing them (though it's implied that this may actually be thanks to a mutation in the bacteria that causes vampirism, rather than the drugs). With their condition stable they have begun to rebuild society and exterminate the undead vampires. In a note, Ruth says that her new species is likely to kill Robert along with the undead and begs him to leave, but instead he stays behind and tries to fight, becoming mortally wounded in the process. Before he dies, he looks out of the bars of his cell and comes to the same conclusion that Smith's version of the character does in I Am Legend's original ending:

They all stood looking up at him with their white faces. He stared back. And suddenly he thought, I’m the abnormal one now. Normalcy was a majority concept, the standard of many and not the standard of just one man.

Abruptly that realization joined with what he saw on their faces - awe, fear, shrinking horror - and he knew that they were afraid of him. To them he was some terrible scourge they had never seen, a scourge even worse than the disease they had come to live with. He was an invisible specter who had left for evidence of his existence the bloodless bodies of their loved ones...

Robert Neville looked out over the new people of the earth. He knew he did not belong to them; he knew that, like the vampires, he was anathema and black terror to be destroyed... A new terror born in death, a new superstition entering the unassailable fortress of forever.

I am legend.

There's a strong argument to be made that I Am Legend's alternate ending, in skewing closer to the ending of the book, is better than the version that ended up in theaters. It completes the story's arc from Robert Neville being portrayed as the sole surviving hero in a world of evil, to the revelation that he's actually the boogeyman that has been preying on a new, emerging race of intelligent beings. Many of the best villains in fiction believe that they are the hero, but I Am Legend is a book that makes the reader believe it too.

More: I Am Legend’s Biggest Change From The Book Broke The Movie