Visually, IMAX producer-director Greg MacGillivray tells a hell of a story. Contrasting the vivid multicolor diversity of healthy, thriving reefs with the bleached desolation of dying coral ecosystems, "Coral Reef Adventure" makes its case with stunning imagery. Docu's auditory elements are less developed. Pic should continue to wow auds.

Visually, veteran IMAX producer-director Greg MacGillivray (“Dolphins, “The Living Sea,” “Everest”) tells a hell of a story. Contrasting the vivid multicolor diversity of healthy, thriving reefs with the bleached desolation of dying coral ecosystems, “Coral Reef Adventure” makes its case with stunning imagery. Unfortunately, docu’s auditory elements are less developed — awkward, old-fashioned stabs at dialogue plus a monotonal “easy-listening”-type track consisting mainly of Crosby, Stills and Nash oldies get in the way of the startling visual flow. Nonetheless, pic’s big picture overwhelms such petty grievances, and gorgeous and thought-provoking “Adventures” should continue to wow audiences at IMAX screens in museums and theaters nationwide before it slides easily into ancillary smaller-screen venues.

The threatened worldwide extinction of coral reefs, a vital source of food, medicine and unparalleled natural beauty, certainly doesn’t lack dramatic punch. Narrative framework of docu sees underwater photogs Michele and Howard Hall recruited as actors as they are summoned to help a friend in Fiji concerned with the decline of the coral reef that sustains his village.

Hang gliding to the rescue (gliders and ultra-lights are a favored mode of aerial transport, allowing spectacular swoops over mountain ranges and overviews of reefs), the Halls embark on a 10-month investigative expedition, soon meeting up with “fish nerd” Richard Pyle and Jean-Michel Cousteau, son of the famed oceanographer.

Starting with Australia’s magnificent Great Barrier Reef, the explorers record the amazing variety of ocean life supported by a flourishing reef system, from eddies of darting silvery fish to high-fashion black-and-white-striped cousins to the cobra. The fantastic shapes and colors of the coral also impress — the red-veined fans, swaying tentacles and pulsating flower-like beds which open and close in symbiotic harmony.

A few Disneyish sound effects occasionally mar the natural flow (a shrimp’s excavation of a home is accompanied by decidedly uncrustacean grunts and groans), but there’s nothing hokey in the strange inter-species moment when Michele Hall apprehensively opens her mouth to angular little creatures that live off plankton in larger fish’s mouths and allows them to clean her teeth.

Drama abounds. In Polynesia, divers are forced into a narrow channel with hundreds of the gray sharks. But other sensational turning-points are treated with less imagination and immediacy. Howard Hall’s near death from the bends is, for some reason, recounted in past tense by his wife.

Coral reefs, unlike other endangered species, don’t simply disappear — they die and their leviathan corpses lie bleak and barren. Some of pic’s most compelling footage follows an octopus on a dying coral reef, spreading its body to enfold and suck out whatever living creatures remain, repeating the process over and over every few feet.

Equally well conveyed is the speed with which a coral reef, thousands or even hundreds of thousands of years in the making, can die. Time-lapse photography traces the draining and bleaching of a large section in a matter of weeks. Film’s message is amply clear: These largest living structures in the world, home to 25% of the Earth’s marine life, have been around for 60 million years but might be all but gone in three decades. Part advocacy plea, part ecological rescue saga, pic’s sharp-edged IMAX lensing, accompanied by Liam Neeson’s voice-overed ominous stats, are plusses that make up for the pedestrian, kid-level script.

Coral Reef Adventure

Production

A MacGillivray Freeman Films production in association with National Science Foundation, Museum of Science, Boston, National Wildlife Federation, Lowell, Blake & Associates and Museum Film Network. Produced by Greg MacGillivray, Alec Lorimore. Executive producers, Charlton Reynders, Christopher Palmer. Directed by Greg MacGillivray. Written by Stephen Judson, Osha Gray Davidson; narration, Jack Stephens.

Crew

Camera (color, 15/70 large format), Howard Hall (underwater), Brad Ohlund (topside); editor, Judson; music, Crosby, Stills & Nash. Reviewed at American Museum of Natural History, N.Y., April 8, 2003. Running time: 45 MIN.

With

Michele and Howard Hall, Rushi Valakoro, Richard Pyle, Jean-Michel Cousteau. Narrator: Liam Neeson.
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