The best Spiderman villains are relatively ordinary people who come undone in the face of some tragedy or personal failure, taking to crime as a result. That is to say their situation is not unlike that of Peter Parker (Tobey Maguire), but the difference between how Peter handled Uncle Ben's murder and how many of his foes reacted to their challenges illustrates the difference between them and Peter. Despite this however, many of these villains -- such as the Vulture, Dr. Octopus, Hydroman, or the Scorpion -- preserve some aspect of the sympathetic loser, and it is hard not to feel a twinge everytime their capers come to nought and they are led off by the cops. Even those villains who do not fit within this paradigm -- the Kingpin, the Green Goblin or the Lizard, for instance -- typically do not have schemes of world-domination in mind and remain refreshingly earthbound, preserving a human scale that is lost when one moves to (e.g.) the Fantastic Four villains, such as Doctor Doom or the Super Skrull.
But then there are the likes of Venom: although his human component Eddie Brock ostensibly is just another loser down on his luck, his persona was never developed enough in the comic books to make him anything other than a one-dimensional villain, and one could never shake the feeling that Venom's raison d'etre was to brazenly capitalize on the fans' desire to see the alien symbiote from Secret Wars I (1984), that bonded with Peter and became his nifty black costume endowed with all sorts of cool powers, return to active duty (in the comics, once Peter figured out that his new costume was more threat than ally, he parted with it using the aid of church bells in a memorable sequence from Web of Spiderman #1 that Spiderman 3 pays homage to). Venom, in short, always struck me as a mere cash cow -- that he was first conveniently introduced in time for the twenty-fifth anniversary of Spiderman comics (in The Amazing Spiderman #300 (1988)), and that he kept making re-appearances every few months (typically in time for The Amazing Spiderman's summer bi-monthly schedule as opposed to the regular monthly schedule, a Marvel innovation from around 1988), didn't help. I never warmed to this villain, and the gimmickry was subsequently ratcheted up a notch with the introduction of Carnage, yet another uninspiring spinoff of the alien symbiote storyline (a perusal of the relevant Wikipedia entry shows that long after I stopped following Marvel, the company had no shortage of lame-sounding follow-ups).
The preceding two paragraphs illustrate just what is wrong with Spiderman 3, and what the film nevertheless manages to get right. For Venom is here, and left me as unmoved as ever. But Flint Marko (Thomas Haden Church) is here too, one of the most sympathetic Spidey villains ever, a petty thief with a sick daughter and hence an urgent cash need, who is one accident away from being transformed into the Sandman (yes his superpower is exactly what his moniker makes it sound like). And in a nutshell, Spiderman 3 works best when it focuses on the Sandman, and least when it focuses on Eddie Brock (Topher Grace) and the alien symbiote. In the movie, Brock is a news-photographer rival of Peter's, his career ruined when Peter exposes a Spidey picture Brock has taken as doctored. Brock has a mad on, and fortuitously stumbles upon the alien symbiote just when Peter is tearing himself away from it. From then on the Brock/symbiote composite ("Venom" in the comics) does nothing much other than cackle, leer, and jump around, all of which makes for quite a drag. He even manages to make the Sandman uninteresting, and the climactic battle between Spiderman and Harry Osborne (James Franco) (who begins this movie villainous, then -- one amnesia-inducing accident later, is good again, then villainous again, and then finally... but you get the picture, don't you?) on the one side, and Venom and Sandman on the other, is distinctly underwhelming. The special effects are all stellar, but the imagination that can make cinema out of computer software is glaringly absent. Mercifully, the same cannot be said for the scene heralding Marko's transformation into the Sandman: as the wind sifts through the pile of sand that is all that is left of Marko, the sand makes several attempts to form into a humanoid figure, each attempt ending in failure as the outlines collapse back into the anonymity of the sand heap. But Marko won't give up, and his desire to be there for his daughter wills him to rise from and with the sand, trademark green striped T-shirt (as all fans of the comics will remember) intact. This is stirring stuff, and cinematic adaptations of comic books do not get much better.
The climactic battle is preceded by vintage Parker-ishtyle heartache, some of it the product of Peter's personality change after he bonds with a strange black substance that jumps him and "becomes" his costume. The "new" Peter is supposedly a darker figure, but the sequences meant to show us this are almost too farcical for words -- I know summer vacations have begun, but honestly does Hollywood need to be this puerile? The moments between Peter and Mary-Jane (Kristen Dunst), or between Mary-Jane and Harry, are par for the course given the preceding two movies, but the effect is marred somewhat by the fact that too much attention appears to have been paid to Peter's romantic relationship, and by the sheer multiplicity of plot threads in the film (including one that inexcusably makes a bimbette of Gwen Stacy (Bryce Dallas Howard)). In sum, Spiderman 3 suffers from attention deficit disorder, and by focusing on too many different things doesn't get any one of them as right as it should. Maybe there will nevertheless be a Spiderman 4, but I won't be holding my breath, unless there's a new director on board. Sam Raimi has done a good job with the trilogy overall, but the franchise is showing signs of fatigue, and could -- like Spidey's black costume -- use a re-invention or two.