A mentally tortured hero, dealing with issues of revenge and pride, must save his ladylove from villains who’ve dangerously dangled her from a skyscraper under construction.

Sounds like Sam Raimi snookered a studio into a big-budget remake of Darkman. That might have been a summer-season kickoff preferable to his overcrowded, underwhelming Spider-Man 3. A bigger bankroll, and a smaller soul, is thrown at a finale that apes his lesser-seen 1990 film.

There’s a reason why stories about this (hopefully final) installment of the superhero series discussed whether co-writer-director Raimi and actors Tobey Maguire and Kirsten Dunst would return in the future. Dead eyes and ideas show anything more from them would just be a paycheck.

Spider-Man 3 is a browbeating domino effect of more, more, more — supporting characters, subplots, villains, running time, instantly forgettable action scenes. While it’s easier to see what’s going on amid all that at-great-heights swinging, it’s harder to care as the massive equation cancels out what made this series so great.

Children in crowds calling Spidey’s heroism “wicked cool” weren’t needed before. Audiences felt that way in once they exhaled after the parade attack of No. 1 or the runaway train of No. 2.

Of course, our rooting interest in Spider-Man, and nerdy alter ego Peter Parker, wasn’t really the spectacle of eradicating bad guys. It was the empowerment of one really good guy. Forcing Peter to come out on the other side of arrogant pride and cold-blooded revenge is a strong starting point until the film introduces countless copouts and rewrites past events to suit current needs.

These days, Peter Parker (Maguire) introduces himself as “your friendly neighborhood … y’know.” Few know he’s Spider-Man, but he’s worked through hero angst to get to the core of the Big Apple’s heart. Splashy civic celebrations can go to even a modest guy’s head.

Mild egotism isn’t helping matters with his failing-actress girlfriend Mary Jane (Kirsten Dunst). She’s wondering if photo-op kisses with blonde bombshell Gwen Stacy (Bryce Dallas Howard, far too good for window-dressing) are for show or for real. Mary Jane doesn’t even tell Peter when she’s panned and canned from a Broadway show (rightly so, given Dunst’s colorless singing).

None of this bodes well for Peter’s planned proposal with a ring handed down by Aunt May (Rosemary Harris). Jewelry isn’t all from her past that’s on his mind, as they learn escaped convict Flint Marko (Thomas Haden Church) confessed behind bars to being the real killer of Uncle Ben. It’s a face-slap to David Koepp’s script for No. 1 that it’s been changed just to introduce a new foe.

Marko’s mawkish introduction shows he’s stealing only to fund operations for a dying daughter (absent after the first reel). When on the run, it’s best to look out for gigantic holes in the ground that are experimental particle accelerators able to fuse DNA with sand. Church has a nothing part, but without Marko, there’d be no brilliantly done special effects for the newly named Sandman. (A scene when he arises from a pile of still sand is more affecting than anything else in the movie.)

Another irritant is Harry Osborne (James Franco), sullen son of the late Green Goblin who knows Peter is Spider-Man and believes he killed his father. Naming himself New Goblin and flying on a silly boogie board, Harry is close to avenging his father when a head injury leaves him with, yes, short-term amnesia. It’s a clumsy excuse for bad foreshadowing and a Willem Dafoe cameo, and it’s not long before Harry woos a flip-flopping Mary Jane with omelets and Chubby Checker.

Not enough for you? Try Edward Brock Jr. (Topher Grace), a frosty-haired freelance photographer poaching Peter’s “exclusive” pictures of Spider-Man at the Daily Bugle. Grace greatly sells the entitlement this sniveling worm thinks he deserves. It’s a shame Raimi’s stated disdain for the villain Brock becomes marginalizes the actor for much of the 140-minute running time.

Venom is a creature with big eyes and bad teeth born from the same black goo plaguing Peter Parker. Yes, another villain. Mucky-muck from outer space has attached itself to Peter’s body and his soul, a symbiotic organism that’s enhancing his arrogance and anger.

Spider-Man 3’s biggest embarrassment is what passes for a consumptive darkening of Peter’s demeanor. Pale, clad in black and sporting emo bangs, he struts down the street with a white man’s overbite, orders around a nice girl next door, gets drunk and — gasp! — knocks poor Mary Jane to the ground. Neither Maguire’s nor Dunst’s expressions suggest fast-fading desperation of a couple in trouble, and what should be horrifying when he pushes her to the ground is an indifferent yawn.

If Spider-Man 3 is meant to evoke jazz’s free flow, Raimi forgets that inspired improvisation isn’t the same as throwing everything at the screen at one time. The only benefit to this fractured focus is Bruce Campbell’s cameo as a snooty maitre d’ will one day make a great YouTube video.

Villains unite. Bonds break. Butts shift. Other franchises have grown as depressingly empty and impersonal, but not in just five short years. If choices make us who we are and we can always choose what’s right, the creative forces at work here should move on.

With their great power has come great laziness, and any identifiable humanism, perfectly melodramatic villainy or wide-eyed wonder at Spider-Man’s abilities is now candy-colored crud.