In "Intimate Agony," the ABC Monday Night Movie at 9 tonight on Channel 7, a seaside resort community is menaced by a cunning subversive terror that strikes without warning. One man endeavors to combat the threat, but a local civic leader tries to stifle his warnings because he fears they will be bad for business.

The plot may sound a trifle familiar. "Agony" has just about the same story line as "Jaws." This time, however, the role of the shark is played by herpes simplex II. The noble avenger is not a police chief but a visiting doctor who takes over for the resort's regular physician during a summer of considerable discontent; the nervous official is a real estate developer (played in full sneer by Robert Vaughn) who doesn't want news of a herpes "epidemic" to spoil the naughty fun of his clientele or cut into condo sales. With such obvious parallels, it's surprising the producers didn't come up with a parallel title as well, but the possibilities for that will absolutely not be considered here.

Perhaps surprisingly, too--considering the fact that a TV movie on every known disease or social problem is more or less inevitable--"Agony" is well made, believable and worth serious attention. It works as a topical drama on an intellectually and literally painful subject and as a kind of grown-up, sophisticated, national version of the kinds of movies that once were shown to Army recruits--the you'll-be-sorry school of utilitarian cinema.

The writer, Richard DeRoy, never quite suggests that herpes is God's way of saying "Stop That"--that this highly publicized killjoy virus warrants the label "Falwell's Revenge," which one wag has applied to it. The film succeeds in dramatizing the emotional problems that accompany the affliction. They, not the disease itself, are the real scourge, according to the young doctor played in the film by Tony Geary, the soap-op throb who proves here he can do more than smolder and stalk about--although I'm not sure even the most liberal of patients would trust a doctor whose hair looks like that.

A number of cases come to the doctor's attention: Katy Fairmont (Cindy Fisher), who is completely petrified by her encounter with the virus (suggesting she is a regular reader of Time magazine, a chief purveyor, some would say, of excessive fearmongering in reporting on this phenomenon); Tommy the tennis pro (Mark Harmon), a promiscuous swinger who thinks his tenure on "Paradise Isle," the name of the resort, really will be paradise--until the apple bites back; and, most tragically, Nick (Brian Kerwin), who fears telling his pregnant wife (Lori Lethin) that he has contracted herpes as the result of an extramarital dalliance and thereby seriously endangers the life of their unborn child.

Director Paul Wendkos keeps the film on a steady line between purple melodrama on one hand and antiseptic preachiness on the other. While it is pointed out that herpes constitutes "a national epidemic," it also is noted that two-thirds of those who suffer from it never have a second attack. The drama and the lecturing are less about herpes than about guilt, fear, shame and ignorance and the emotional havoc they can wreak. Thus "Agony" makes for a sober and sobering look at the wages of ecstasy.