Pirates of the Caribbean

Shiver me timbers - it's the theme park buccaneers

For years, there have been sequences in Disney cartoons that have had no other purpose than to facilitate a Disneyland ride: whenever you see a character whooshing along on a magic carpet, plummeting into tunnels and dodging lava plumes, you know that the rollercoaster is already under construction. It was just a matter of time before this corporate synergy worked in reverse. And now one of Disneyland's most longstanding animatronic attractions, Pirates Of The Caribbean, has been turned into a live-action movie, the snappily titled Pirates Of The Caribbean - The Curse of The Black Pearl.

Like any theme park ride, the film is a well-oiled piece of engineering with meticulous attention to detail. That might sound like faint praise, but at a time when most summer blockbusters wouldn't know their arcs from their elbow, it's a cause for celebration that POTC-TCOTBP isn't a senseless scrapheap. Gore Verbinski, the director, and Jerry Bruckheimer, the producer, have delivered a decent family adventure movie with a beginning and an end, and more than its share of good jokes in the middle. Kudos should go to Ted Elliot and Terry Rossio, the screenwriters. They're the team behind Shrek, The Mask Of Zorro and the Aladdin cartoon, so they're veteran craftsmen when it comes to sword fights, unlikely heroes and beautiful-yet-spirited damsels in distress.

Geoffrey Rush plays Barbossa, a scurvy sea wolf who once stole a casket of Aztec gold. As luck would have it, the Aztecs' magic was more potent than you'd think, considering how they finished up. The gold was cursed, and Barbossa and his men have been condemned to an eternity of living death. In sunshine or darkness, they look like your common or garden scoundrels and knaves, but by moonlight, they're putrefying corpses. The only way to lift the curse, Barbossa thinks, is to attack a British colony and kidnap the governor's daughter (Keira Knightley). Her father (Jonathan Pryce) and her well-born suitor (Jack Davenport) are the kind of wig-wearing British toffs who are never capable of anything gallant in a Hollywood film, so the job of saving the girl is left to a blacksmith (Orlando "Legolas" Bloom) who secretly loves her, and a pirate (Johnny Depp) who used to sail with Barbossa.

Depp has a grand old time camping it up as Captain Jack Sparrow. More and more when I see him in a film, I enjoy his efforts to distract us from his perfect cheekbones by trying out an odd accent or a bizarre costume, but I don't believe in the character he's playing for a moment. True to form, in Pirates Depp turns his back on every previous screen buccaneer, from Douglas Fairbanks to Captain Pugwash, and instead takes Keith Richards as his inspiration. Wearing dreadlocks, apparently waterproof eyeshadow, and a forked, beaded beard, Sparrow seems to have been left befuddled and wobbly by years of pillaging and plundering - or, possibly, propping up the bar in a Soho drinking den. But he still retains a dandy's peacocky affectation, and he's still able to talk himself into and out of trouble, with a slurred English gurgle that does sound a lot like Richards, and even more like Tommy Cooper.

As long as Depp is on screen, we have almost as much fun as he must have had on set, but Elliot and Rossio slipped up when they tore the role of the hero into two halves. They've given the Depp half too much personality, so that he's more of a caricature than a character, and they've given the Orlando Bloom half not enough personality, so he has less complexity than his Errol Flynn beard. That said, Depp, Bloom and Keira Knightley (from Bend It Like Beckham) are all outrageously easy on the eye. They'd have to feature on any top ten list of the world's prettiest people, and if the film had sailed by at a sufficient rate of knots, that alone might have kept us rooting for them. But Pirates Of The Caribbean - Curse Of The Black Pearl is as long-winded as its title. At well over two hours it gives you more than enough time to realise that you don't care what happens to anyone in it.

It's puzzlingly unthrilling for a film with so much action. There are cutlasses everywhere, but the fight scenes have been edited into such tiny shreds that you can't tell how they fit together. And although not more than two minutes pass at a time without someone firing a cannon or escaping capture, there are no stunts that would find houseroom in an Indiana Jones or Jackie Chan film.

Maybe Pirates is just staying true to its theme park roots. Once you've admired the engineering, you get tired of how mechanised it all is - how the stalactites in the cavern are made of plaster, and how the people look as if they can be switched on and off with a lever. Certainly, the film is most effective when it keeps away from reality altogether. The only proper thrills and chills are provided by the cursed corsairs. As they step in and out of the moonlight (which is conveniently piercing, even at the bottom of the sea), they flicker back and forth between ragged cadavers and human beings. It's a spine-tingling effect that should give your children nightmares. Barbossa's men may be undead, but they bring Pirates Of The Caribbean to life.

n.barber@independent.co.uk