"World War III" -- some fun! It's almost enough to make you look forward to World War IV.

First Super Bowl Sunday, now "World War III"; out of the frying pan, into the crock pot. NBC is bringing out the big guns for the February ratings sweeps; they can't get much bigger than "WW III," a suspenseful, high-impact, two-part TV movie airing tomorrow and Monday at 9 each night on Channel 4.

Viewers expecting a laser-zapping big bang will be disappointed; although there's plenty of well-shot action, the film is not a special effects spectacle like "Things to Come." But it is in the thoughtful doomsday vein of films like "Fail Safe" and "Seven Days in May." Its scenario of how America and the Soviet Union stumble to the brink of global holocaust could be dismissed as farfetched, but not if one bothers to look back on events of the past 20 years. Or the past 12 months. Or whatever.

Similarly, though one is tempted to snicker when, onto the screen, pops a credit reading, "and Rock Hudson as the President," the tee-hee is stifled when you stop to think who the real president is. Besides, Hudson does the best acting he's done on the screen since his harrowing performance in the superior sci-fi film, "Seconds."

In the tense and crackling script by Robert L. Joseph, the requisite ominous wheels are set in motion by a slightly deranged Soviet official who authorizes a mad act of sabotage by a small regiment of Russian troops who are sneaked into Alaska for the purpose of doing something nasty to the oil pipeline. This is in retaliation for a U.S. grain embargo. It can't hurt the movie's credibility that the Reagan administration is considering such an embargo right now.

Naturally, the film is meant to be a cautionary tale, and there is one scene, in part two, of soldiers attempting to beat swords into plowshares that may make cynics groan and right-wingers run for their Di-Gel, but the scene has an organic sweetness to it, like the photo of a hippie sticking a flower in a gun's barrel in the 1960s. The movie's bleeding heart is in the right place.

Comfortingly, perhaps, the final cut of the film eliminates the original year chosen for Armageddon by Joseph: 1987 (this will be news to TV "critics" who put too much stock in press releases). Instead, "WW III" takes place in that vast terrain known only as "The Future." Except for a little extraneous baggage involving a romantic subplot between David Soul, as an Air Force colonel, and Cathy Lee Crosby, as an intelligence officer, there's relatively little of the usual TV movie padding here. You're pulled along swiftly and surely to the moment when a certain finger reaches for a certain button.

Also worth noting in the cast is Robert Prosky, that hardy perennial of Arena Stage, who plays a rather sinister Soviet official -- but only "rather" sinister, because this saga of Cold War brinksmanship pretty much blames the system, or human frailty, for the tumbling dominos that bring one and all face to face with the specter of extermination.

This attractive production about apocalypse proved to be somewhat ill-fated. The original director, Boris Sagal, died in a helicopter accident while shooting early footage near Mount Hood, Oregon, which doubles for Alaska in the film. The talented David Greene took over for Mr. Sagal on one week's notice. The film is dedicated to Sagal's memory. Hudson suffered a heart attack after completion of the film and didn't work again for months.

Greene gives the picture a forward drive that is rare in TV movies but really essential to this kind of chillerdiller fantasy. In the tricky business of keeping up momentum over such a long period of time, he is invaluably assisted by composer Gil Melle's inventive and unusual musical score, which puts an ominous coating of melancholy dread over the action.

Not so melancholy and dreadful that the film isn't fun, however. Viewers who think they've seen enough snow to last them six or seven lifetimes may not be thrilled at all the arctic scenery, but the picture has the snappy seductiveness of a good paperback political potboiler. Let the record show that "World War III" was very adroitly waged.