B-

Imagine a cross between one of the innumerable monster-on-the-loose movies made by American International in the fifties—though with much improved visual effects—and “E.T.,” and you’ll have some idea of what J.J. Abrams’ tribute to his own cinema-obsessed childhood is like. “Super 8” is enjoyable enough as pure popcorn fodder, but also terribly derivative and overblown.

It’s set in 1979 Ohio, and instead of the teens who were invariably the heroes of the old AIP cheapies, it focuses on a neighborhood group of middle school chums who intend spending the summer making a super-eight-mm. zombie movie. The director is chubby Charles (Riley Griffiths), but the main character is cute-as-a-button Joe Lamb (Joel Courtney), an assiduous model-maker who assists his best bud Charles by doing the make-up on the cast. Others in the group include gangly leading man Martin (Gabriel Basso), brainy extra Preston (Zach Mills) and firecracker-obsessed, prodigiouly-braced mini-zombie Cary (Ryan Lee, whose antic persona brings John Megna to mind).

Joe is working on his pal’s summer project in spite of the fact that he’d suffered a terrible loss only months before—the death of his beloved mother in a work accident—and his dad Jackson (Kyle Chandler), a deputy sheriff, is an emotionally remote fellow who’s in pain himself. And his situation only deepens when Charles enlists pretty Alice Dainard (Elle Fanning) in their project. Joe’s obviously infatuated with her, but she’s the daughter of gruff drunkard Louis (a conspicuously shaggy Ron Eldard), whom Jackson blames for his wife’s death and who reciprocates the lawman’s hostility.

Amidst this backdrop of small-town emotions—the suburban cacophony of which Abrams (like Spielberg before him) captures in scenes of familial disorder, particularly the ones set in Charles’ house—the plot kicks in when the kids are filming at an old railway station one night and a train coming by crashes because a pickup truck driven by one of their science teachers deliberately derails it. That leads to the arrival of troops under the command of nasty Colonel Nelec (Noah Emmerich), the disappearance of local people (including the sheriff, leaving Jackson in charge, and Alice), the mysterious theft of mechanical devices and wiring all over town, an evacuation order, and the realization by the kids, once they get a chance to look at the film they shot at the station, that the train was carrying something very strange and dangerous.

Abrams’ script is a real farrago, with scenes of rowdy adolescent horseplay that might have come out of “Stand By Me” to big action set-pieces that wouldn’t be out of place in an Arnold Schwartzenegger vehicle (that train crash sequence goes on for so long, with so many explosions and barrages of flying debris, that you have to snicker when none of the kids suffer anything but a few smudges of grime on their faces). The subplots about puppy love and bridges built between warring families add the obligatory note of sentimentality. The final shots of awe-struck faces looking skyward have “E.T.” and its myriad imitators written all over them. And at its core the scenario is just a variant of the Area 51 stuff that’s the basis of movies, TV shows and comic books, complete with nefarious government agents—and with a smidgen of old horror flicks like “Tarantula” thrown in for good measure, and even an echo of “Blow-Up.”

But though it won’t earn any points for originality, in Abrams’ hands “Super 8” is a slick package of hand-me-down goods, smartly put together and so efficiently executed that even gaps in the plot (why doesn’t Joe investigate that cemetery shed earlier, or why does the creature keep the humans it’s captured in cocoons?) don’t matter much. Courtney is an agreeable young hero (however implausible his escapes might be), Fanning a touching heroine, and their fellow classmates (especially Lee) all amiable types. The adults, by comparison, are basically one-note figures, and neither Chandler nor Eldard can do much beyond hitting the required notes.

And by and large it looks good, although Larry Fong’s cinematography shows some blemishes (what are those blue streaks in some of the night scenes?), the effects aren’t always topnotch (with the creature, when finally revealed, looking pretty artificial), and Michael Giacchino’s score is rather bland.

Overall, though, “Super 8” works smoothly in the pattern of a picture like “WarGames,” and can be enjoyed as a high-tech updating of fifties schlock like “The Blob” or “Invasion of the Saucer Men” in much the same manner that “Alien” treated “It! The Terror From Beyond Space.” Parents should be warned, though, that some of it may prove too intense for young children. The creature here doesn’t play nearly as nicely as E.T. did, and its movie is unlikely to be embraced as warmly as Spielberg’s was.