Yet another unnecessary reboot hits theaters this week, with a fewgood action sequences, but marred by one-dimensional characters andexcessively shaky camera work.

Early in Red Dawn (** out offour; rated PG-13; opening Wednesday nationwide) residents of Spokane,Wash., wake up to paratroopers floating in, as if suspended on palemushrooms. Soon, the shooting, strafing and explosions begin.

Asin the 1984 original, the heroes are predominantly teenagers - mostlymembers of a high school football team - led, in this superficiallyupdated version, by a soldier who had fought in the Iraq War.

Thepremise is that enemy forces - North Koreans and Russians - haveinvaded the USA without warning. It quickly becomes an all-outoccupation. People are taken prisoner, and most choose to fearfullycooperate. But not these feisty teenagers. Under the tutelage of Jed(Chris Hemsworth), the older brother of Matt (Josh Peck), who plays onthe Wolverines football team, they escape to the woods and learn tofight like the toughest Marines. Their training takes mere days. Theseteens are soon firing all manner of weapons, setting up elaborateambushes and detonating bombs as if they were seasoned combat veterans.

Butthere's never any real depiction of how these kids are actually coping,separated from family, friends and any vestige of their former lives.Are they scared, determined, ambivalent? The movie doesn't bother to gothere. Similarly, collaborators choose their path with no explanation.

Thorstar Hemsworth is credible as the unofficial leader of the overnightsoldiers, convincing as an action hero and believable in hisüber-patriotic speechifying. Peck as his brother is far lesseffective, with an acting style that would be better suited to a remakeof Bill and Ted's Excellent Adventure.

The fighters beginto resemble a rural militia, dubbing themselves the Wolverines. It'sessentially a shoot-'em-up spectacle devoid of any moral complexity.

Fire first and never ask questions seems to be their motto.

Thefilm features some taut action sequences, well choreographed bydirector Dan Bradley, who is also one of the top stunt coordinators inthe industry. But scenes are rather murkily shot and characters are likecardboard cutouts.

These young guerrillas eventually meet up witha trio of roving Marines. Oddly, they are the only hint of nationalmilitary forces around, though their leader (Jeffrey Dean Morgan) speaksof swaths of unoccupied territory "from Alabama to Arizona and Michiganto Montana." Apparently, the invading evildoers are scared off byalliteration.

Only those with paranoid fantasies of an en masse invasion on American soil will find Red Dawn remotely powerful. The concept should have been updated to allow for more complex and surreptitious kinds of warfare.

Any episode of Homeland is far more terrifying.