2007's I Am Legend, starring Will Smith, is often discussed as a zombie movie, but that's not actually the case. The Francis Lawrence-helmed film was an adaptation of Richard Matheson's 1954 post-apocalyptic novel of the same name. The book was one of the early apocalypse stories, and one of the novels responsible for normalizing the concept of global pandemics and infection-type stories in pop culture. The plot sees the sole survivor of a post-apocalyptic disease set out to find a cure.

The film version faithfully adapts parts of the book, but I Am Legend's ending is quite different to the novel, as are its Darkseekers, the creatures who are at the center of the story alongside Smith's Robert Neville. The film enjoyed a successful commercial run and even gave viewers a superb, realistic performance from Will Smith, and its survival plot and horrifying monsters mean that the movie is often lumped into the zombie genre. That, however, is incorrect.

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While I Am Legend is, at times, reminiscent of the likes of The Walking Dead or 28 Days Later because of how the Darkseekers appear physically, they're not to be mistaken for zombies. In Matheson's original novel, the monsters inhabiting the post-infection landscape are supposed to be vampires. They were intelligent creatures not too dissimilar from humans. In Francis Lawrence's adaptation, he names the monsters as Darkseekers, but never divulges what type of creature they are. They do have similarities to the vampires in the book, however; for this reason, they're more reminiscent of Matheson's creatures than undead zombies.

Will Smith in I Am Legend deleted scene

As well as this, the main reason that I Am Legend is not a zombie movie is that zombies are, conventionally, creatures that are reanimated once a person has died. They're undead, coming back to life. In Lawrence's retelling of the story, his creatures don't do this. They're not actually dead at all. Instead, the Darkseekers are just victims of the outbreak in I Am Legend; they're ill but, more importantly, they can be cured.

Vampires were the route that Ridley Scott wanted for his unmade I Am LegendFrancis Lawrence also revealed that he wished his I Am Legend stuck closer to the novel in that regard. A large part of the novel's ending is reliant on the fact that the creatures are vampires - something the film changes entirely, sadly making for a worse finale. There were talks of an I Am Legend sequel before that got shut down; a reboot has also been discussed since. If that is the case, perhaps that version of I Am Legend will be more clear in establishing the fact that its creatures are vampires. While Francis Lawrence's adaption doesn't do that, the monsters in his I Am Legend certainly aren't zombies.

Next: I Am Legend's Alternate Ending Explained: What Happens & Why It Was Cut