Coming from the same creative team behind the first two Spider-Man movies — headed by director Sam Raimi — the big question hanging over part 3 is: what the hell went wrong? Spider-Man 3 seems to have been willed into existence by the combined efforts of marketing departments, merchandise divisions and third-party licencees. The result is soulless and witless, a sequel too far.

Demurring to Netiquette, be warned there are spoilers ahead.

The motor here is the precarious three-way relationship between Peter Parker (Tobey Maquire), Mary-Jane Watson (Kirsten Dunst) and New York City. Peter has the annoying habit of dashing off to save NYC from all manner of pesky superbaddies the minute M-J comes round for a cup of tea and cuddle. Peter’s former best pal is Harry Osborne (James Franco), who believes Spiderman killed his pa (at the end of the first movie, continuity buffs). Harry dons pa’s Green Goblin disguise and sets out for revenge, planning to destroy Peter and M-J’s relationship and steal her for himself before killing Peter. Meanwhile, a slimy cosmic symbiote inhabits Peter, amplifying his anger and badness, apparently turning him into a member of Panic! At The Disco in the process. Elsewhere, crook-on-the-lam Flint Marko (Thomas Hayden Church) gets zapped at the local particle research facility and becomes a creature made entirely of sand. Topher Grace plays an unscrupulous photographer with eyes on Peter’s job at the Daily Bugle, and Bryce Dallas Howard looks fantastic as a shameless plot device to make Peter realise how much he rilly, rilly loves M-J. Theresa Russell turns up for, ooh, three minutes and acts everyone off screen.

OK, so what’s wrong here? Plenty. Frankly, I’m fatigued by comic book adaptations. The skies have been gridlocked with caped heroes flying hither and thither, speeding to save major American cities — real and imagined — from cackling hoardes of genetically mutated ne’er-do-wells. In the last few years, we’ve had movie versions of (deep breath) Superman, Batman, Spider-Man, X-Men, Incredible Hulk, Fantastic Four, Ghost Rider, V For Vendetta and Hellblazer. Soon come: FF2, Iron Man and fresh installments of the Batman, Hulk and Superman franchises. The multiplexes are at saturation point with four-colour freaks and weirdoes punching each other through buildings and saving hapless extras from death by taxi cabs hurled randomly across streets.

The problem is that all these movies conform to roughly the same plot. To wit: saving city/planet/loved ones from evil person. At one point during Spider-Man 3, as a snarling newspaper boss rages at a mild, mannered cub employee who hides a secret identity as a superhero, I thought I’d slipped through the Fourth Wall and into a Superman film — such is the woefully limited genetic pool on offer here that characters and storylines replicate themselves like pernicious rogue DNA.

According to the remorseless, two-dimensional logic of the superhero genre — where More Is Good — it follows that one pitched battle between hero and villain must then be followed by an even bigger one. So it is that for Spider-Man 3, the film climaxes with a WWF-style smackdown between Spider-Man, Green Goblin, Sandman and Venom (that’s the alien slime, folks). Do we need 4 baddies in a movie?, I whine. Why can’t we just have Spider-Man facing down Green Goblin, thus resolving a narrative arc begun in the first film in a clean and satisfying way? Why clutter it with more supervillains? Because, say Marvel/Sony’s mechandise divisions (in a voice I imagine to sound chillingly like the HAL computer in 2001), we can sell more action figures in Burger King! I slam my head repeatedly against the nearest wall and cry openly for all of our children, even those as yet unborn.

Of course, I blame Sam Raimi. In fact, I blame Sam Raimi, Christopher Nolan, Bryan Singer, Ang Lee and a whole other bunch talented folks who’ve squandered their brilliant talents on making the superhero genre respectable these last few years. Damn you — why can’t you just go and originate your own movies! Or go and make a movie based on a comic book with zero awareness in the outside world — like American Splendor or A History Of Violence. They were good movies, right..?

There’s nothing in Spider-Man 3 to suggest Sam Raimi directed it. It feels like a movie made by committee, driven by a financial imperative. A quick skim round Google tells me that the first movie took $807m in global ticket sales; the sequel took $783m. And that’s without the revenue from DVD and ancillary rights. Who can blame Marvel and Sony from wanting to make even more money? They’re businesses, after all! Making money is their job! Lots of money! Ah, but they set the bar pretty high by getting Raimi involved. If they’d given it to a journeyman hack like, say, Brett Ratner, then I wouldn’t bat an eyelid if the film was a disaster — in fact, I’d be disappointed it it wasn’t — there’s nothing I like more than having my prejudices confirmed. But Raimi can do much better than this. He appears to have been totally emasculated by the financial needs of these two large megacorporations.

Now, if only there was a superhero on hand to save Sam Raimi…

Spider-Man 3 opens in the UK on May 4