"Terror Among Us" may mark TV's first mass rape, though milestones like that are probably not worth marking. The CBS film, at 9 tonight on Channel 9, concerns a disturbed delivery man who, in a rage, ties up five women in a room, beats them and either rapes or threatens to rape them all.

There are superficial resemblances to the case of Richard Speck, convicted of murdering eight student nurses in Chicago in 1966; all the women tied up are stewardesses, and in a valiant effort to signal for help, one of them (Sarah Purcell) throws herself through a plate-glass window.

The film, produced by David "Police Story" Gerber, is properly unnerving and not as sensationalistic as it could have been. But there's something questionable about using such volatile material as the basis for a mere cop saga in the first place. The program will be preceded with a parental advisory, and that is more advisable than usual.

Don Meredith plays the cop tracking down the rapist (Ted Shackelford), a parolee whom he suspects will go wrong again, and Jennifer Salt plays a parole officer whose liberal views on criminal justice are trashed when the parolee first murders his shrewish wife and then rounds up the women for assault.

The Meredith-Salt alliance suggests there are series aspirations afoot and brings to mind the Clint Eastwood-Tyne Daly partnership of "The Enforcer," although of course Meredith hardly has the commanding presence of Eastwood, and Salt lacks the critical charisma of Daly.

Both actors are required to stop in hallways or in the office for long debates about crime and punishment. "The system may not be perfect but without it, we have nothing," she says. "The system!" he growls later. "I have had it up to here with the system. There are too many of you protectors who are overly concerned with his [the criminal's] rights." And so on.

These rhetorical donnybrooks seem to function as lofty justification for depicting, graphically for TV, violent sexual crimes, but at no time does the film exhibit the thoughtful approach to urban violence of such TV movies of the past as "The Law" or "The Marcus-Nelson Murders." Perhaps the producer, director and writers should not be blamed for this. Maybe it's The System.