``The Rock'' is a first-rate, slam-bang action thriller with alot of style and no little humor. It's made out of pieces of othermovies, yes, and not much in it is really new, but each element has beenlovingly polished to a gloss. And there are three skillful performances:Sean Connery is Mason, an intelligence expert who's been in prison for30 years; Nicolas Cage is Goodspeed, an FBI scientist, and Ed Harris isGen. Hummel, a war hero with a mad scheme to wage chemical warfareagainst San Francisco.

The plot hook is a mission to break into Alcatraz. Harris andhis men have occupied the former prison island, taken civilian hostages,and threatened to fire deadly rockets at San Francisco unless theirdemands are met. What are the demands? Hummel, who has three PurpleHearts, two Silver Stars and the Medal of Honor, is angered that 83 menhave died under his command and never been recognized, because they wereon secret missions that the government denied even existed. He wants$100 million in payments to their next of kin.

Hummel is known and respected in Washington, and his demandsare taken seriously. A news blackout is imposed while the Pentagonassembles a team to break into Alcatraz and neutralize the poison gasmissiles. We've already seen Goodspeed think fast while sealed in anairtight chamber with a deadly chemical bomb; now he's assigned to jointhe task force, even though he's basically a lab rat with minimal fieldor combat experience.

Another key member of the team is Mason, a British spywho, we learn, successfully stole all of J. Edgar Hoover's secret files(``even the truth about JFK's assassination'') before being secretlyjailed for life without a trial. Mason's qualification: He is ajailbreak expert who is the only man ever to escape successfully fromAlcatraz.

Movies like ``The Rock'' progress from one actionsequence to another. Sometimes it doesn't even matter much how they fittogether. Consider, for example, the highly entertaining way in whichMason turns a haircut into an opportunity to dangle one of his oldenemies by a cord from a top floor of a hotel. And the way that leads toa San Francisco streetcar chase inspired by ``Bullitt,'' leading to acrash almost as sensational as the train crash in ``The Fugitive.'' Strange, isn't it, that after going to all that trouble toescape, Mason allows himself to be recaptured almost passively--probablybecause unless he joins the team, there's no movie. Strange, too, thatalthough it has time for unlimited action, ``The Rock'' never slows downenough for a scene you might have thought was obligatory, in which Masonhas the plan explained to him, along with a pitch about why he should goalong. (He has a motive, all right--his only child is in San Francisco,and could be one of the poison victims. It's just that the movie neverquite bothers at this stage to tell him, formally, about thepoison.) The break into Alcatraz owes something to Don Siegel's``Escape from Alcatraz,'' the 1979 Clint Eastwood movie. While that onenegotiated the maze of tunnels under Alcatraz in murky darkness,however, ``The Rock'' provides Alcatraz with a subterranean labyrinth aslarge and well-lighted as the sewers in ``The Third Man'' and as crammedwith props and unidentified metallic machinery as the ``Alien''movies.

The plot moves efficiently between firefights, explosions,torrents of water, hand-to-hand combat, interrogation, torture,imprisonment, escape and scientific mumbo-jumbo, as the infiltrators tryto stop Harris' men from wiping out 70,000 San Franciscans, and thePentagon prepares to firebomb the island with planeloads of ThermitePlasma, which sure sounds neat. All of these elements are standard issuefor action thrillers, but the script adds some deft touches (asked if heknows why he has been released from prison, Connery wryly said, ``I'vebeen locked up longer than Nelson Mandela. Maybe you want me to run for president.'').

What really works is the chemistry between Connery, as areluctant warrior who has all the skills necessary to outsmart andoutfight the occupying force, and Cage, as the nerd who can disarm therockets but is not much in the killing department. And then there is anintriguing complexity added to the Ed Harris character, who is not asone-dimensional as he seems (early in the film, he advises some smallchildren touring Alcatraz to return to their tour boat).

There are some loose ends. Cage and Connery keep turning updry when they should be wet. A White House aide gently says, ``We need adecision, Mr. President''--after the deadline has passed--and gets aspeech so long it could have cost the 70,000 lives. And of course theheroes are allowed to eavesdrop as needed on any conversationscontaining information they need to know.

In a movie that borrows from all the movies I've alreadylisted (plus second-hand filching from ``Die Hard'' and related epics),there are two particularly obvious steals: the oldhypodermic-needle-plunging-into-the-heart trick, from QuentinTarantino's ``Pulp Fiction,'' and the Mexican standoff in whicheverybody has a gun pulled on everyone else (from QT's ``ReservoirDogs'' and ``True Romance'' courtesy of old Westerns). Two lifts fromTarantino? Maybe the producers, Jerry Bruckheimer and the late DonSimpson, were getting their revenge for the famous Tarantino monologuein ``Sleep With Me'' where he analyzed their ``Top Gun'' as a homosexualparable.

No matter. Director Michael Bay (``Bad Boys'') orchestrates the elements into an efficient and exciting movie, with some big laughs,sensational special effects sequences, and sustained suspense. And it'sinteresting to see how good actors like Connery, Cage and Harris canfind a way to occupy the center of this whirlwind with characters whosomehow manage to be quirky and convincing. There are several IdentikitHollywood action stars who can occupy the center of chaos like this, butnot many can make it look like they think they're really there. Watching``The Rock,'' you really care about what happens. You feel silly laterfor having been sucked in, but that's part of the ride.