"Eclipse" might be as good as the "Twilight" films are going to get. The main actors have settled comfortably into their roles in this third installment of the franchise. Jackson Rathbone, Nikki Reed and Ashley Greene, the more interesting of the home-team vampires, have a welcome new prominence, and Robert Pattinson even has a scene in which he displays a twinge of character-development. The movie also has some actual action, as everyone must know by now — a big vampires-versus-vampires-versus-werewolves battle sequence at the end of the picture.

However, having imposed something like narrative clarity on the story, new director David Slade is still stuck with the story — which, deriving as it does from the paceless goop of Stephenie Meyer's books, and having been wrestled into a script by Melissa Rosenberg, is a threadbare quilt of pre-teen romantic clichés padded out unconscionably with long character flashbacks and rambling dialogue that's deader than any of the vampires in attendance. (The picture runs two hours, and might have been more enjoyable — and certainly less exasperating — if it had been cut down into a one-hour TV special.)

We begin where the last movie left off, with chaste young lovers Bella Swan (Kristen Stewart) and Edward Cullen (Pattinson) nuzzling in a sunlit flowery field. She's reading him poetry. He's glistening a bit, as the "Twilight" vampires ridiculously do whenever they're out and about in the daytime. He asks her to marry him. "Change me," she replies — meaning, turn her into a vampire, too. He doesn't want to do this. But we already know that, and we wish he'd just get over it and get it over with, because we've been through this wearying routine before, and we know lots more of it lies ahead.

Bella's dad (Billy Burke) doesn't like her hanging out with Edward so much. Why can't she spend more time with the other kids, like that nice Jacob Black (Taylor Lautner)? Jacob, of course, as we also know, is a member of the local werewolf clan, and he's in love with Bella, too. Possibly in vain, though. "I don't feel that for you," she says. "I don't buy it," he snaps. Then he tries to kiss her, and she punches him in the face. (And sprains her hand — werewolves are very ... hard, or something, apparently).

You could count the minutes Lautner doesn't spend topless in this picture on the hands of a cartoon character. ("Doesn't he own a shirt?" says Edward, deploying one of the movie's several self-aware wisecracks.) This is an understandable strategy on the part of the filmmakers, since Lautner, a formidable physical specimen and a mildly appealing presence, does most of his acting with his abs. (True, he hasn't been given a lot to work with by the script, but who here has?)

Jacob and Edward's territorial sniping over Bella continues even after the need arises for both of their families to band together against an attack by the rogue vampire Victoria (now played by Bryce Dallas Howard) and her army of "newborns" — vampires who've only recently been turned. Here we puzzle once again at Stephenie Meyer's complete indifference to traditional vampire lore — to the basic characteristics that make these creatures fun. Apart from the fact that her bloodsuckers can walk around in the sunlight and have no fangs, we're now informed that newborns are the most powerful of all vampires because they still have traces of human blood running through their veins. Traditionally — logically — the most ancient vampires are the most powerful. And anyway, don't most vampires have human blood coursing through them? Isn't human blood what they live on? The contending vampire contingents in this movie could as easily be rival biker gangs or feuding hillbilly families with little adjustment required in the story.

This brings us once again to the sex question. There comes a scene where Bella and Edward are canoodling on a bed, and she asks him — begs him, actually — to have sex with her. But after a quick montage of button-fumbling, Edward backs away. "Believe me, I want to," he says. "I just want to be married to you first." Then he says, "I'm from a different era." If I had to guess, I'd say that era was the 1950s, when sex, if it happened to rear its troublesome head, was consummated offscreen, following a tasteful fade-out. In the "Twilight" films, carnal possibilities aren't even implied. No one's saying that Bella and Edward should get naked, in the manner of HBO's immeasurably superior "True Blood" series. But their dinky cuddling and cooing has no erotic charge. It's like a pepperoni pizza without the pepperoni. It's all cheese.

Just as our patience with this picture is about to collapse — following mini origin stories for two of the Cullens, and a meandering campfire chat with the tribal elders of the Black clan, and a scene in a tent with Bella, Edward and Jacob that may still be going on, for all I know — we finally get the big battle between the local vampires and werewolves and Victoria's invading army of newborns. The werewolves are meticulously animated CGI (although as always in "Twilight" land we wonder how guys in pants can transform into pantsless wolves and then transform back again to guys in pants). But the battle itself is oddly earthbound — the two groups of antagonists simply charge across a field at each other and collide. There's lots of thrashing and gnashing and flying through the air, but what this smackdown summit of vampires and werewolves boils down to is a big street rumble.

The people behind the "Twilight" films clearly feel that fans will sit through anything that brings the books they love to the screen. I wonder how long that'll hold true, though. Could this really be as good as the series is going to get? Without ever getting good?

Don't miss Kurt Loder's review of "The Last Airbender," also new in theaters this week.

Check out everything we've got on "The Twilight Saga: Eclipse."

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