Network news boys like to pretend they know nothing about show business, or at least that they're not in it, so CBS News approaches the motion picture industry on tippy-toe with "Inside Hollywood: The Movie Business," a 90-minute special to air at 8:30 tonight on most CBS stations but not until midnight Sunday on Washington's errant CBS affiliate, Channel 9.

Charles Kuralt hosts the report and one of the first mistakes made by producer-director-writer Perry Wolff violates what should be a CBS News dictum: Never acquire Charles Kuralt to walk around a set on camera. He moves like a herd of gazellas.

In fact, the set isn't needed at all, any more than the childish, animated graphics that suggest cut-rate Monty Python. Wolff seems stymied by TV's inability, or his inability, to cover very well a story that takes place in shuttered boardrooms and at expense-account lunches: the wheeling, dealing and reeling of movie financing. But he does take viewers to such privileged locales as the fancy-shmancy watering hole Ma Maison, its parking lot choked with Rollses, and the set of the forthcoming movie version of E. L. Doctorow's "Ragtime," another of those strife-torn extravaganzas.

The script doesn't appear to know that the nature of movies has changed in the past 20 years (Kuralt calls them an "art form" -- only as compared to television, surely) but concedes the audience has. It's mostly kids now, and kids whose television saturation compels them to seek gigger and splashier thrills from movies. Kuralt and Wolff don't entertain the notion that television has ruined the movie business -- a good case could be made -- nor even take into account the burgeoing new home video markets that give moves extended lives and figure into financing.

They do report that only one out of 10 movies is a hit, that the average movie last year cost $4 million and this year costs $10 million, that "The Empire Strikes Back" returned 1,300 percent on its investment, and that the colossally mismanaged "Heaven's Gate" (known in Hollywood by the scandal-conjuring nickname "Heavensgate") cost $38 million and so far has brought in a teensy $38,000 at the box office, having been pulled for re-editing immediately after its initial release.

The name of former Columbia Pictures executive David Begelman does not come on the report, the matter of creative bookkeeping is not examined, and changes in America's leisure time patterns aren't dealt with very deeply; the money Americans spend on movies is compared to how much they spend on horse races, a meaningless statistic. Nobody points out how the percentage has changed over the years.

Wolff keeps trying to make the fact that he couldn't get the story a part of the story, an old "60 Minutes" trick. Motion picture exectives wouldn't talk to CBS News about deal-making, Kuralt says (well, who do they think they are?). Not even CBS entertainment executives would talk. But crews did capture on film Frank Price, head of Columbia Pictures ("If you have a picture they want to see, they show up") and former 20th Century-Fox president, now independent producer, Alan Ladd Jr., an amusingly taciturn grouch.

Scenes from such forthcomers as "Cannonball Run," a can't-miss brawl with Burt Reynolds, are shown, along with such likely stiffs as "Legend of the Lone Ranger." And the Histories of such box office smasheroos as "The Blue Lagoon" and "Kramer vs. Kramer" are recounted. While ignoring the possibility of hanky-panky in Hollywood, the report deals at some length with the illegal practice of exhibitor fraud, in which theater owners hold out on movie companies. It is not mentioned that movie companies make thier terms so tough that exhibitors are often left holding the bag on flops and with only the most minimal returns from hits.

But a Holyoke, Mass., exhibitor does say that he makes more money from concessions than admissions and he recalls nostalgically that "Jaws' was a spectacular eating film."