I have nothing against zombie movies, it’s the zombies themselves that I can’t stand. I’ve always hated their proscriptive familiarity, their lazy illogicality and the idea that people who came back from the dead would instinctively develop an impractical cannibalistic bloodlust and chase after helpless human victims for no other reason than that it makes for diverting screen entertainment.

This year has been agony so far. We’ve had high-profile zombie knockabouts with Planet Terror, 28 Weeks Later and 30 Days of Night – all movies bloated with the bodies of their undead protagonists, sometimes shuffling, sometimes sprinting, but always chewing and spewing gore for the sake of the genre and the pulse-quickening thrills of the front-row fanboys.

I Am Legend, on the other hand, is a zombie movie with a difference. Perhaps aware of the genre’s central limitation, it is positively resistant to revealing the true nature of its creature killers until the last possible second. Instead, under tight direction from Francis Lawrence, and from a hugely economical script by Akiva Goldsman and Mark Protosevich (based on Richard Matheson’s 1954 novel of the same title), we get a beguiling portrait of ache and isolation in postapocalyptic New York.

Here a soldier and scientist, Robert Neville (Will Smith), is the seeming sole survivor of a rapacious viral outbreak (a cure for cancer gone wrong) that has devastated the population of the entire planet. Neville, in a delicate and restrained turn from Smith, is introduced to us while hunting for food with his beloved Alsatian, Sam, along the corridors and chasms of an entirely empty Manhattan. The depiction of the eerily overgrown city is one of the first genuine and unobtrusive testaments to the groundbreaking power of computer-generated effects in years.

Neville’s days, we soon discover, are divided between hunting, physical exercise (Smith reveals a massively pumped bod in a showcase chin-up scene), scientific research in his basement laboratory, and some dalliances on the brink of madness (he talks to some store dummies and flirts with others – which, given the circumstances, is hardly a crime).

At night, however, Neville’s Washington Square home becomes a veritable fortress, and he hides in a protective huddle with Sam, in an empty bathtub, while outside terrifying howls and sinister screams imply the presence of an evil beyond imagining. This presence, we eventually discover through carefully moderated flashbacks, is of course, the zombie faithful – human beings who have been transformed by the virus into light-sensitive night-stalkers with a super-violent bloodlust. And yet, just like the shark in Jaws, their conspicuous absence from the action makes their first few appearances, in tiny snatched glimpses from the shadows, and in a terrifying chase through a darkened warehouse, utterly chilling.

This is, nonetheless, a studio blockbuster, and as the need to flaunt production values eventually overrides the desire for dramatic tension, I Am Legend overplays its hand. Somewhere in Act III, the movie goes zombie crazy. Computer-generated zombies, as rubbery and unconvincing as Spielberg’s shark, dash about the city with superhuman powers and wait to get shot and burnt by Smith’s gun-toting nemesis.

It’s a disappointing end, naturally, but possibly inevitable, given the nature of the genre. And still, the preceding film has been so compelling and so curiously involving that ultimately it hardly seems to matter.

15, 101mins

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