Poses some interesting questions, but does little to answer them

Rating: 7/10 (29 December 2007)

From the opening scene with Emma Thompson (uncredited), the intelligent moviegoer knows what's next. What's not to so obvious is why Will Smith is the last one on Manhattan island. Manhattan is a crown jewel and to think that all the uninfected/immune people would simply flee the island as fast as their feet would take them versus introducing the subhuman infected to Smith & Wesson is not clear. Now granted, just Will Smith versus all those humanoids is a losing prospect from the beginning. But given a small, immune, heavily armed contingent with floodlights, I am sure Manhattan would be infection free in a matter of weeks, not years.
Now 1.5 million people live on Manhattan. If 90% are killed by the virus that leaves 150,000. Supposedly 90% of those not killed become infected. That leaves 15,000 immune versus 135,000 ravenous, belligerent infected. Now you may think the odds are overwhelming, but if you study the Spanish conquest of the Mayan civilization you will understand why gunpowder was invented and why numbers are irrelevant when your foe is unarmed.
Now granted, I Am Legend is not about how Will Smith ended up all alone three years after the outbreak, but one does wonder how he managed to survive all those years on his own. The movie does posit the potential of the infected somehow becoming smart, devious, cunning or what have you, as is the question of isolation a la Castaway. But while interesting, they are subplots to the larger theme of Will's quest for a anti-virus.
Now I am not going to criticize the Will Smith's of the world who rather find a cure versus kill 'em all. But my gut tells me that if such a scenario ever truly played out, the real conflict would be in the politics of those who wanted to extend compassion versus those who had another agenda and I doubt that they would wait for an election.