Mediocrity of 'The Beach' not all DiCaprio's fault

''The Beach'' is a mediocre movie, to be sure, but it would be a shame if blame were laid exclusively at the undoubtedly sandy feet of its titanic star, Leonardo DiCaprio.

Skeptics scoffed when the quintessentially American ''Leo'' -- as DiCaprio, post-''Titanic,'' is now known around the world -- was cast as Richard.

The sought-after role is that of an English drifter at the unnerving heart of the 1996 best-seller published when author Alex Garland was a scant 26. But DiCaprio isn't British, which seems to have necessitated a shift in tone from the unsparing nihilism of the novel. Americans, or so the thinking goes, don't do bleak.

Then there was what one might call the McGregor factor. Whereas Ewan McGregor was key to the earlier films of the creative team behind ''The Beach'' -- ''Shallow Grave,'' ''Trainspotting'' and ''A Life Less Ordinary'' -- even the Scottish actor's newfound status as a ''Stars Wars'' icon wasn't enough to displace DiCaprio when it came to casting.

So how is Leo? Not bad actually, which is more than can be said for a script from John Hodge that scuppers most of the novel's tension.

While the book may not quite be the modern-day ''Lord of the Flies'' that admirers have claimed, Garland nonetheless proved on his debut outing that he can write a page-turner with the best of 'em. It's a clipped, often violent, ultimately very chilling novel about a time-honored topic -- paradise postponed -- here reinvented anew. A 20-something drifter in search of utopia, Richard finds himself a near-casualty of an impossible ideal in a community of foreigners that could not be more dystopian.

''I carry a lot of scars,'' Richard reports twice in the last page of the book. And so he does, even if readers are likely to be most disturbed by the matter-of-fact blankness that is the narrator's principal means of reportage.

From its opening moments -- ''my name is Richard,'' we are told, ''so what else do you need to know?'' -- the film sounds as if it wants to catch that moral aphasia.

The surprise, then, is how quickly the script lapses into cliche.

''We were headed for the great unknown,'' says Richard, as he and two newly acquired French friends, Francoise (Virgine Ledoyen) and Etienne (Guillaume Canet), abandon their Bangkok dive for a mysterious island locale mapped out for Richard by the (literally) haunting Daffy (Robert Carlyle, reprising the psycho turn he perfected last year in ''The World Is Not Enough'').

They encounter sharks, waterfalls and gun-toting Thais before arriving at an island retreat overseen by Sal (Tilda Swinton), the beach's resident despot, whose officiousness co-exists with a strong sexual appetite.

Does the beach offer any kind of balm? Not much, although Danny Boyle's direction is at its strongest juxtaposing the supposed idyll with a return visit to mainland Thailand -- here seen as urban life at its most disorienting and jagged.

For that sequence, all credit too to cinematographer Darius Khondji, whose images are every bit as jarring -- and, when need be, alluring -- as they were in ''Evita'' and ''Seven.''

In the novel, readers felt each incremental step in the breakdown of ''society'' into its component savage parts, many of them embodied by Bugs, Sal's supposed main squeeze.

But as the movie progresses, it seems to have other interests, from a soft-core underwater tryst involving our leading man to evoking the odd twinge of ''Jaws'' that comes with fending off fins.

And although DiCaprio is certainly a good enough actor to suggest goodness gone AWOL, no one should have to deliver musings like ''I tried to remember the person I used to be, but I just couldn't do it.''

DiCaprio is far more effective in various off-the-cuff moments -- hissing, shockingly, at a newly arrived American tourist whose tenancy on the beach will turn out to be brief, indeed. Or in his sweaty realization, at the eleventh hour, that even paradise exacts its own horrific price.

That glimpse into the abyss echoes ''the horror! the horror!'' of Joseph Conrad's ''Heart of Darkness,'' one of ''The Beach's'' numerous literary antecedents.

It's a shame, then, that the movie opts instead for the kind of spurious messages that are delivered far more meaningfully in, among others, ''American Beauty.''

''I still believe in paradise -- it's not where you go,'' concludes Richard, who decides instead that such states of grace consist of ''a moment'' that, once found, lasts forever.

''American Beauty'' suggested as much with the mere sight of a plastic bag dancing in the wind. In ''The Beach,'' by contrast, such considerations merely sound waterlogged.

''The Beach'' is a 20th Century Fox release of a Figment Film, produced by Andrew Macdonald. In a move sure to frustrate DiCaprio's teeny-bopper brigade of fans, the film has been rated R. Running time: 120 minutes.