"Inchon" is scarcely the first movie of its kind to make an unintentional mockery of an authentic, dramatic military operation.

It's difficult to imagine a movie like this lasting commercially for longer than a week or two, even if evangelist Sun Myung Moon, officially credited as a "special advisor" on the troubled and costly ($40 million-$50 million) production, should decide that viewing is compulsory for followers.

Fairness demands that "Inchon" be dismissed as a trifling offense as bungled war epics go -- less of an insult to history and discriminating moviegoers than monumental klunkers like "Tora! Tora! Tora!," "The Battle of Britain" or "Midway." Nevertheless, the sad specimen opening today at area theaters reveals some piquantly freakish features, not the least of them being Laurence Olivier's excruciating yet morbidly fascinating impersonation of Gen. Douglas MacArthur.

The most obvious and abiding defect displayed by "Inchon" is a ramshackle form of story construction in which the desire to fit The Little Picture inside The Big Picture achieves only wholesale trivialization. The Little Picture consists of scattered, truncated sequences which keep losing the whereabouts of the principal fictional characters -- Ben Gazzara as a marine officer, Maj. Frank Hallsworth; Jacqueline Bisset as his estranged wife, Barbara, and Richard Roundtree as his strangely solicitous, chummy subordinate, a gunnery sergeant called August Henderson -- in the aftermath of the North Korean invasion of South Korea in June 1950.

The Big Picture is devoted to stilted, semi-historical episodes with MacArthur and his staff members as they formulate plans for the daring, amphibious assault at Inchon, the port city just west of the South Korean capital of Seoul. The last triumphant gambit of MacArthur's career, the operation was designed to reverse the tide of battle in Korea by swiftly recapturing Seoul and cutting the supply lines of the overextended North Korean invaders.

The outbreak of hostilities finds Maj. Hallsworth in Inchon professing his honorable intentions to a Korean sweetheart of intimidating dignity (Karen Kahn) and trading philosophical platitudes with her father, an ex-soldier played by Toshiro Mifune. Mrs. Hallsworth is in a village somewhere north of Seoul scouting native handicrafts for her interior decorating business when the sound of North Korean armor obliges her to hail a cab and join the panicky exodus of refugees to the south.

Despite the seriousness of the situation, the filmmakers seem incapable of sustaining any melodramatic urgency about the flight of Mrs. Hallsworth and the rather desultory efforts of the major to locate her. Part of the problem stems from Jacqueline Bisset's appearance; it's a little difficult to concentrate on the peril to her character when the camera is so fixated on her cleavage.

Each update on Mrs. Hallsworth seems to cue a gratuitous atrocity sequence, with the North Koreans inflicting fresh outrages on helpless victims. These interludes are always awkwardly inserted and redundant. Also, there is a stronger emotional impulse behind the atrocity snippets than anything else in this sluggish, dithering movie. The suspicion arises that the impulse may be traceable to the film's Special Advisor.

Silly as her presence is, Bisset at least serves a tangible scenic purpose. While Gazzara and Roundtree meander about, it's impossible to figure out what sort of marines they're supposed to be or where they belong. The absent-minded continuity tends to lose track of everyone in mid-scene. At one point we leave Gazzara and Roundtree suddenly as they jounce along a railroad track in a jeep, evidently sitting ducks for an approaching Mig. When next seen, they're somewhere else, and it must be days or maybe weeks later. That unresolved cliffhanger remains a permanent baffler.

Eventually, Maj. Hallsworth is identified as a weirdly versatile, freelancing member of MacArthur's staff. At one juncture he's discovered in telephone conversation with the general, transmitting a ringside account of the retreat of the South Korean army. Later, he emerges as a commando and frogman on the eve of the Inchon invasion, supposedly securing a lighthouse whose beacon will be indispensable to the fleet as it enters the treacherous harbor. As if that weren't enough responsibility, he must help clear the channel of mines, too.

It's typical of the film's slipshod approach to storytelling that after insisting on the fiction that "the entire operation, the entire mission" depends on keeping that lighthouse beacon functioning, we see the light get shot out but never see how it's made operational again in time to guide the ships into harbor. Is it being picky to mention that this seems rather a crucial oversight?

Proportion and judgment are not in plentiful supply in "Inchon." For example, the depiction of an authentic catastrophe, the demolition of the Han River Bridge at Seoul while it was clogged with refugees, is immediately trivialized by shifting attention to a bogus aspect of the situation -- will Jacqueline Bisset's taxi, now carrying five cute refugee kiddies, slip into the drink or barely escape disaster? In a similar respect, Gazzara's irregular shenanigans reduce the combined contributions of strategists, infiltrators, commandos, naval gunners, jet fighter pilots and riflemen to a few make-believe grandstand plays.

This reductionism falsifies more than the battle itself. The potential human drama is also minimized to the non-issue of reconciliation between the preposterous major and his missus. Under the circumstances, one greets the episodes with MacArthur as diverting historical camp, if not stirring historical reenactment. Olivier, looking dreadfully emaciated, cuts such a cadaverous figure as MacArthur that you can't take alarmed eyes off him.

One of the cruel ironies of "Inchon" is that it reminds you Olivier was once considered for the title role in "MacArthur" that eventually went to Gregory Peck. As things have turned out, Peck was a more convincing, if far from commanding, image of MacArthur. In addition, the Inchon invasion was presented more effectively as a mere episode in "MacArthur." To the question, "Is this ersatz war movie really worth a few laughs?," the answer inevitably comes back a resounding negative.