In "Spider-Man 2," Our Hero wears his heart on all eight sleeves.

All right, an exaggeration: Peter Parker (Tobey Maguire), better known as Spidey, never actually turns into an arachnid, and never has need of more than two sleeves, but the movie has eight sleeves' worth of heart.

That's good, not bad. In fact that's very good. It shows that all concerned in the second installment of this mega-franchise -- most important, director Sam Raimi, returning from his love-labor of the first one -- have looked hard at the success of the original and have understood and preserved its core.

Which is to say that "Spider-Man 2" may be the most internalized superhero vs. monster movie ever made. Though buildings crumble, an arachno-man swings, an octo-man crushes and the earth trembles, it's really about what's going on inside, where each of the antagonists mulls fate vs. character, wishes things were otherwise, wants more, settles for less, and generally carries on like Holden Caulfield walking around the East Side in that goofy hat all those years ago.

Oh, and incidentally, the movie cleverly solves one of the most difficult technical issues of the monster movie in a way no film ever has.

But more on that later.

Let's begin with Peter Parker. He's still a kid -- when he's 77, Maguire will look like a kid -- with a quivery voice, a forlorn look of befuddlement and anxiety, a boy's tentative way of moving, and doubts about self and destiny. And he is still in love.

Pete lives with his aunt -- the great Rosemary Harris -- and his heartstrings go bing-bing-bing over the girl next door, except that she's become a model and an actress and no longer lives next door on Staten Island but in swanky Midtown digs. It helps if you have a thing for ex-child star Kirsten Dunst, and I don't, so I have to fake it here. To my ungrateful eyes, Dunst has flat hair and a wan face; she could have used some orthodontia as a child as well, if she hadn't been so busy acting. But that aside, the movie's central emotional tussle is the doomed, yearning love between Pete and Mary Jane. When one is available, the other isn't. And now that she's high-powered in the glitzy artistic-fashion world, and he's, er, delivering pizzas by day and saving the city by night, it looks like they'll never get it together. But each looks and weeps for what might have been, so the movie is built on a hollow ache in the heart that even we non-super people feel once in a while. (Unless you're a critic, of course; we weren't issued hearts.)

Meanwhile -- it's fair to chide the film for repeating the plot device of the first -- a genius scientist, Professor Otto Octavius (Alfred Molina), is trying to develop a new energy source under the sponsorship of Peter's rich-boy pal Harry Osborn (James Franco), who is the son of the villain of the first picture, Norman Osborn (Willem Dafoe). Dr. Octavius's technology goes very wrong -- 'splosions, flames, 'lectricity -- killing his wife and a legion of anonymous lab assistants and turning him into an angry metal freak: that is, a man with four gigantic prehensile arms harnessed to his nervous system, capable of incredible strength, violence and agility. This puts him in a very bad mood, and before you can say "Good lord, Myra, it's alive," he's off on a destructive toot, expressing his rage at his failure.

Okay, kids, what's the problem solved?

The problem is this: In most monster movies where the sub-theme is man-becomes-monster, the monster ends up being so different from the man that you feel nothing for it. It's new, it's different, it's not affiliated with the man before it. It has no emotional connection to the investment in empathy you've already made in the picture. This problem is ubiquitous; most famously, it undercut the end of the original "Terminator," where -- his flesh and Arnold Schwarzeneggerian mug melted away -- the Terminator was just a clanking metallic gizmo of no emotional resonance. It was like watching a fight between Linda Hamilton and a can opener.

Here, the brilliance of Raimi is that Molina never ceases to be Molina; his face doesn't disappear in some larger amorphous mass. His body doesn't go away. He's always Molina: It's Molina's character, his malevolence as reflected in his snarl, the black hubris of his eyes, the droopy flop of his old-guy body, the vitality of his nasty line readings. Okay, so? The guy's got "It Came From Beneath the Sea's" gigantic tentacles affixed and if he wants, he can slap the Chrysler Building into a pile of rubble.

This sets up a number of arachno vs. octopod confrontations in downtown Gotham, or in a computerized version thereof. Who knows how they do this stuff? What is important is that it's pretty believable, more on the strength of the dynamism of the movement (which is the most authentic thing about the sequences) than on the verisimilitude of the characters. To my eyes, Spidey and Doc Ock in action up there beyond the 75th floor never cease to be slightly rubberized, artificial objects. But the cutting is so sinuous and breathtaking, the music (by Danny Elfman after too much coffee) so onrushing and the camera so penetrative of the depths and heights of midtown Manhattan at cloud level, that the illusion, despite its artificiality, works. You don't believe it but you "believe" it.

The best of these effects involves a runaway elevated train, with Spidey atop it, flinging out cables of web to brake the momentum, and Ock urging it onward toward a track that ends, depositing the contrivance in midair, Spidey aboard.

Maguire, with his dim eyes (he must be the least expressive good actor in Hollywood) and his forlorn voice, gives the movie an emotional center utterly rare for this sort of thing. You can love "Spider-Man 2" and not hate yourself in the morning.

Spider-Man 2 (127 minutes, at area theaters) is PG-13 rated for dynamic, bloodless pop violence.

Somewhere in there, in addition to Tobey Maguire, is a sensitive man-boy looking for love who won't let archvillains or skyscrapers stand in his way.He's only inhuman: As Doc Ock, Alfred Molina is the multi-tentacled, multi-talented foil to Tobey Maguire's Spider-Man.