When I Am Legend forgets that it’s supposed to have a plot, it is one of the greatest science fiction films ever made. But about three-quarters of the way through the film, it remembers that indeed! This is supposed to have An Ending, with An Emotional Climax! And with this revelation, it ratches up the Contrive-O-Meter, ratcheting away from the compelling story of a desperately lonely man fighting for survival to turn into predictable Hollywood schlock.

The story of I Am Legend is simple: A cure for cancer has mutated into a deadly virus that has killed 95% of the people on Earth. The remaining 5% have turned into light-sensitive vampires who need blood and are destroyed by ultraviolet light.

The sole survivor? Robert Neville, scientist and army Colonel, who remains at the site of the outbreak – New York City, which has been dead and rotting for three years.

He is a man of strict routine; it’s the way he fights against the emptiness of having no other people and no hope. He gets up in the morning, does exercises (and displays a sculpted body that could turn a straight man gay), goes down into his laboratory basement to try to cure the virus (which could revert vampires to normal men). Then he goes out to hunt through the ruins of New York.

What’s happened to New York City is breathtaking. The film’s at its best when its looking over the decay of civilization, the lush overload of billboards and signs suddenly overlaid with rot and plants. It looks like the grave of all humanity, the final legacy on its way out by nature, and the visuals are spectacular.

Neville is, sadly, also going insane, which is clearly shown when he goes to the video store. He has one faithful companion – a beautiful, friendly dog named Sam, who is his only contact with other people.

I Am Legend is absolutely genius when it is just exploring the life of the last survivor on Earth. Watching Robert Neville’s routine crumble as the loneliness takes him is some of the most compelling cinema around; he has all the material goods he could want, but not a person to share it with, and the sheer number of comforts he’s built up tells you how much time he’s spent there. Neville has a military temperament and a fierce willpower, but everything he loved, every last hope, has been taken from him. He’s stubbornly convinced he can fix it, but we only believe he can because this is a movie and miracles sometimes happen.

It is a look into the damned.

Unfortunately, the film is handicapped somewhat because it’s based on a book. And the book of I Am Legend has one of the best endings in all of science fiction/horror, turning everything you knew about the man and his world upon its head and producing something grand and glorious. To a large extent, I Am Legend the book is about that rare and unique ending, and so when the movie departs from it it’s a disappointment.

In the book, Robert Neville finds a survivor named Ruth, who he takes back to his apartment. He’s deeply mistrustful of Ruth, and it turns out he’s right to be; Ruth is a vampire. It turns out that some of the infected people have found a way to hold the disease at bay, returning to a more-or-less human state. They have reassembled their own civilization, they have their own government… But as vampires, they’re still forced into their torpor at night, and look no different from the barbaric vampires (whom they pity) while they’re sleeping.

Yet Robert has never stopped hunting.

In his ignorance, Neville has been killing both the saved and the unsaved vampires, and has become a thing of legend. He is now the boogeyman of this new, mutated humanity – the thing that creeps into their house when they are helpless and slaughters them. In fact, he’s held this new vampire civilization in a grip of terror for years. They find him and execute him, but he can’t help but laugh – he’ll be the vampire legend of the vampires, the greatest monster they know.

(END ENDING)

The fact that the ending differs from the book isn’t a fatal one – I don’t demand fidelity in my adaptations, only good movies. Yet if you’re going to yank out one of the all-time classic finales and replace it, then you’d better replace it with something better… Or, at least, swap it in with something that’s as unique as the rest of the movie. But the ending to the movie of I Am Legend feels as though they cut the end out of some other sci-fi movie and plopped it in here wholesale, leaving loose ends galore.

What we get feels vaguely recycled, the kind of heroic climax we’ve seen too many times before. And after the hot newness of the first three-quarters, it’s oddly disappointing to lapse back into Generic Hero Endings 102.

Strangely enough, there are repeated hints in the film that point towards the old ending, perhaps artifacts left over from the original screenplay. There are a few plot points raised that never get resolved by this new end, but would be explained completely by the “classic” ending, making it a strange experience for both the folks who’ve read the book (who caught the hints and wondered) and those who haven’t (who wondered what the heck was going on with that?).

What you get is three-quarters of a great movie with a quarter of an okay ending tacked on. It’s like watching a pole vaulter do a near-perfect vault and then clip the bar with his ankle, knocking this from an A-lister to a perfectly good movie, even an exceptional one…. But not a great one.

You haven’t seen the first part of I Am Legend before. That is, as Barney Stinson would put it, “Legend….ary.” The ending is serviceable. Make your own judgments from there.

(Tell me I'm full of it)