Arnold Schwarzenegger is back, making Rambo look like a refugee from the Folies Berge res. But "Commando," a high-energy feast for cannibals, starts out fun and ends up dreary -- how long can you watch this stony Austrian take target practice?

"Commando" begins with three brutal murders, cuts to Arnold frolicking with his little girl, and there you have it -- you know that, over the next 90 minutes, the murderers will kidnap the girl, Arnold will kill them and save his daughter, and the final credits will roll.

Which is exactly what happens. The victims, it turns out, were former members of a crack commando unit led by Col. John Matrix (Schwarzenegger), who has since come in from the cold. The murderers are led by a Latin American dictator (Dan Hedaya) whom Matrix once overthrew (Matrix was, it seems, "good CIA"); they're using the daughter as bait to get him to assassinate the leader he installed, thus restoring the dictator to power.

Who are they trying to kid? Armed with machine guns, Uzis, .45s, a hunting knife, a rocket launcher, his own elbows and fists, the heel of his hand, a lovely stewardess (Rae Dawn Chong), and a quiver full of oneliners that jam in his Teutonic mouth like pachinko pellets, Arnold introduces them to their maker.

Schwarzenegger is the grimmest of grim reapers, Samson battling the Philistines, with the jawbone of an ass built into his face. That jaw! Standing alone, as proud and rounded as Beethoven's forehead, it seems to be making impossible demands on him; unlike Stallone, whose muscles hang beneath his delicate features like a cheap suit, Schwarzenegger's physique, however astounding, never seems quite up to the demands of that stern promontory of bone.

Schwarzenegger has become the most engaging of the new crop of killing-machine leading men, partly because, outsized and inarticulate as he is, you can't imagine him functioning in civilization. How would "I'd like a tuna fish on rye?" sound, coming from Schwarzenegger? It's easier to see him biting the tuna's head off.

He's King Kong, and here he has two Fay Wrays -- his daughter Jenny (played indifferently by Alyssa Milano) and poor Rae Dawn Chong, who, with her long foal's legs, provides marvelous decoration and some comic flair, but isn't allowed to do much (Arnold, after all, has to Go It Alone). Hedaya, unfortunately, doesn't paint the kind of broad, villainy fun as Gene Hackman, say, did in "Superman"; and the fine supporting psychos, including Vernon Wells (Wez in "The Road Warrior") and David Patrick Kelly, never really cut loose, either. No one's allowed to steal Arnold's spotlight.

Director Mark Lester has framed "Commando" as a comic book: Arnold breaks chains and tears sheets of corrugated steel with his bare hands; he plows an MG into a telephone pole, but although neither he nor the stewardess are wearing seatbelts, neither are injured. Lester doesn't have the sense of visual style that other directors, like Spielberg and Lucas, bring to their comic-book movies; harshly lit and sometimes amateurish (the dummies in the explosions are obviously dummies), "Commando" doesn't last in your eye. And Lester doesn't pace his sequences, allowing the suspense to build -- it's all breakneck, and it tires you out.

What style Lester does have is cribbed from sources as diverse as the movies of Brian de Palma, "The A-Team," and "Rambo," whose success "Commando" obviously intends to repeat; the theme (by James Horner), with its splashy fanfare, is lifted almost outright from "The Long Good Friday."

The sloppy derivativeness of "Commando" can be maddening after a while, as can the same improbabilities that, early on, provided the movie with its wiggy fun. By the end, when Arnold is mowing down wave after wave of soldiers, who obligingly jump up on guy wires, you're sick of the improbabilities, because you know that the biggest improbability of all -- Arnold actually taking it on the chin -- is one you'll never see.

Commando, opening today at area theaters, is rated R and contains considerable violence and profanity.