Here's a math problem for you. Take Apocolypse Now plus The Blue Lagoon divide by Lord of the Flies and multiply by The Mosquito Coast. What's the answer to this equation? It's The Beach, the stumbling new effort from the British team of Danny Boyle, John Hodge and Andrew MacDonald who brought us the psychedelic treat of Trainspotting.

Based on Brit novelist Alex Garland's book, the film stumbles in presenting the themes that were so powerful in Garland's book, relying more on star Leonardo DiCaprio's post-teen star power to keep things moving. Luckily, Leo is up to the task. He's growing into a handsome guy and he certainly spent plenty of time with the weights, preparing to bare his newly swarthy chest. So, where's the substance in all this? Buried in the pretty scenery -- both human and natural.

Garland's book focused on the disenchantment of today's youth, a population looking for bigger answers and a lasting peace. Governed by pop culture, we are all trapped in the modern world. This idea filters loosely through the film with hero Richard (DiCaprio) claiming that he's searching for "something more beautiful, something more exciting, something more dangerous." Aren't we all, in one way or another? Richard's answer is to leave behind friends and family, who we never meet, and head for Bangkok, "the good-time city." He is the quintessential traveler, not a tourist, but a lost soul looking for answers.

In Bangkok, Richard meets Daffy (Robert Carlyle), a fella just this side of nuts, who offers up a map of an island paradise before killing himself to escape the modern world of parasites. So, of course, what does Richard do? He meets up with French couple Etienne (Guillaume Canet) and Francoise (Virginie Ledoyen) and they high tail it to said island. Of course, paradise isn't ever just that. Here, fields of marijuana are guarded by trigger-happy Thai banditos, who have struck up an uneasy alliance with the idyllic community of European nomads that welcomes our heroes on the other side of the island.

What follows is the standard adventure in paradise and, for a while at least, it's a pretty enjoyable ride. In fact, "pretty" is the operative word. In the hands of Boyle and D.P. Darius Khondi, Thai paradise is just that. Simple activities like fishing and swimming in the lagoon or beachfront volleyball and bonfires under the moon take on a magical patina. To make paradise complete, Richard wins Francoise away from Etienne, a distinct departure from the book that gives us the requisite "Blue Lagoon" love scene. Trust me, the teeny-boppers will just love this bit, even if those of us a little older will think we're seeing Brooke Shields and Christopher Atkins.

The fun in the sun, though, is soon eclipsed when leader of the island folk, Sal (a superb Tilda Swinton), learns that, before coming to the island, Richard had made a copy of the map and gave it to a pair of bumbling surf dudes back on the mainland. Will their tranquil sanctuary be found out? If yes, Richard will be held to blame. Here's where the film really falls apart - proving to all build-up and little pay-off, all pomp and no circumstance. While Boyle comes up with some brilliant visual bits, they aren't enough to save the plot's gradual degeneration into pointless chaos.

The blame for this mess seems to land on screenwriter Hodge, who really missed the boat in terms of the thematic focus of the film. Hodge makes The Beach less philosophical journey, more travelogue and episodic melodrama. In the novel, Garland explored in detail why we as creatures of modern society so desperately need utopias, which -- even if we find them-- we will always destroy. This message is hinted at but, in the end, we find ourselves on more of a pleasure cruise than the soulful journey on which the film hopes to take us.