Agent Smith is a virus -- no, really, he's a virus infecting 'The Matrix' and it's up to Keanu Reeves' Neo to stop him. Setting aside the fact that we'd rather not live in a world where it's up to Keanu Reeves to save the day, we have to hand it to Agent Smith for being one hell of a bad guy. He's sort of the modern sci-fi response to the Terminator, using a monotone voice and hiding his eyes behind those sunglasses so we have no idea what he's really up to -- it's just creepy.