he polar ice caps have melted, covering the earth with water. The people who survived this catastrophic environmental event have been forced to adapt to this strange new world – by living on various floating ships and vessels, constantly at sea. An unnamed mariner (Kevin Costner) is one such lucky – or unlucky – survivor, who roams the borderless waters in search of fabled dry land, doing everything he can just to subsist. With various Rube Goldbergian contraptions aboard his tiny raft (as well as a harpoon gun), including a device that recycles his urine into potable water, the drifter must regularly contend with roving thugs, some of whom merely want to steal his belongings, others of whom wish to kill him for sport.

“I’ve seen your boat before; haven’t seen you.” It’s essentially a postapocalyptic water-world of pirates, with pitiable, hardscrabble souls struggling not to succumb to the elements and to each other. But pockets of civilization holed up on atolls prove to be just as dangerous as the wandering “smokers” who murder and steal on the open waters; when humans become this desperate, lawlessness is rampant and life is cheap. So when the mariner stops at an iron-bound stronghold to trade some precious dirt, it’s not long before he’s attacked, imprisoned, and condemned to die. But a timely raid by smokers, led by the merciless Deacon (Dennis Hopper), delays his execution, while two sympathetic members of the community that captured him, Helen (Jeanne Tripplehorn) and Enola (Tina Majorino), may prove to be the answer to his ultimate salvation.

“What, are we barbarians here?” Though it obviously suggests some pertinent commentary on mankind destroying the planet (without dwelling on blame, of course), “Waterworld” is first and foremost an action film. And many of the early sequences are absolutely stunning as the atoll fortress is sacked by a swarm of enemy seacrafts, absorbing bullets, fire, and explosions, forcing the hero to launch a daunting escape and flight. The eye for adventure is keen, aided by excellent stunts and rousing music (by James Newton Howard). It’s even more visually impressive knowing how much of the sprawling sets and rusty vehicles are genuine, strapped and cobbled together like the those in “The Road Warrior,” with a few concepts from “Escape from New York.” The excitement is unexpectedly consistent, at least at the start.

Although it occasionally goes too far, dampening the severity of life-and-death scenarios, the humor is mostly effective and welcome, particularly surrounding Hopper, whose larger-than-life villain is goofy and evil in equal measure. He definitely doesn’t take his role seriously, and it generally works out for the better, allowing him to be more memorable than the rest. Less sensible are the various supporting players who provide their own comic relief, especially when various confrontations that highlight the anarchy and barbarism of limited resources must clash with lighthearted resolutions. Despite the zombie-apocalypse levels of suffering, the adventure-based outcomes are largely bloodless (and toothless).

“Dry land’s a myth.” As the loner seafarer plots a course away from the vengeful Deacon, the story meanders a touch, eating up minutes with the unnecessary reiteration that drifters are dangerous, as well as with a tangent that unrealistically finds Helen surveying submerged ruins. The budget may be considerable – and certainly well-spent on sets and props – but some of the editing decisions don’t build upon the story as much as they stifle the momentum and hurt the pacing (Enola’s continual yapping rarely helps, either); the action at the beginning just wasn’t sustainable. There’s a hint of a love story, too, though it’s of the unbelievable fantasy kind, where intense situations provoke a certain romance. Fortunately, once the finale gets underway (and it takes far too long for that to happen, dripping with sappy speeches about friendship and zealous proclamations of prophetic visions), the return to action is colossal – though not of the same realism and choreography as before. Brimming with shootouts, detonations, and showdowns, the conclusion is rambunctious yet hollow, wrapping up with underdeveloped, hastily-conceived ideas. The falling action is terribly anticlimactic. It’s always a tough sell when the introductory moments are more thrilling and large-scale than the climax.

– Mike Massie