Three TV specials go head to head Sunday

The Last Frontier CBS, Sunday and Tuesday, 9-11 p.m. Stars Linda Evans, Jack Thompson, Jason Robards. There Must Be a Pony ABC, Sunday, 9-11 p.m. Stars Elizabeth Taylor, Robert Wagner, James Coco, Chad Lowe. Witness to Apartheid PBS, Sunday, 10-11 p.m. (Check local listings.) Producer Sharon I. Sopher for Developiong News Inc./Channel Four Television, UK. Made-for-TV entertainment competes with social conscience on television Sunday night.

Two lush, lightweight super-soap operas on commercial television are scheduled against a hard-hitting antiapartheid documentary on public broadcasting.

The dramas offer slick, kitschy diversion at best. The documentary makes no pretense that the viewing will be easy, as it documents the physical and mental torture inherent in South Africa's racial policy.

The Last Frontier might have been titled ``Bonanza . . . Down Under.''

It deals with a courageous, widowed American woman who is determined to make a life for herself and her children in a cattle station in the Australian outback.

The woman, played by ``Dy nasty's'' Linda Evans, falls in love with the outcast son (Australian heartthrob Jack Thompson of ``Breaker Morant'' fame) of the villainous neighboring rancher (Jason Robards) who wants her late husband's acreage. Evans, despite the dusty discomfort of the drought-stricken outback, always manages to look chic, as she fights for her rights.

``Frontier'' tries every trick in the book to hold viewers' interest for four hours. Besides a father-son feud, a jealous sister, a torrid love affair, and the battle for control of the land, there are: a camel race, a cattle stampede, explosions, helicopter chases, crawling snakes, starving livestock, and a spectacular fire. Superb work by cinematographer Ian Baker in Australia's Barossa Valley somehow manages to turn the bleak, arid landscape into ruggedly glorious vistas, but even that can't keep this extravaganza from becoming little more than a cunningly contrived potboiler.

There Must Be a Pony is merely a vehicle for Elizabeth Taylor -- looking slim and more beautiful than ever. But the far-fetched story runs out of gas halfway through. The melodrama revolves around an actress's attempt to rebuild her life after a mental breakdown. Her dependence on the men in her life and her contradictory attempts to control them are what dominate its soapy plot.

Taylor overacts shamelessly in this overheated, overwritten piece. Robert Wagner, on the other hand, underacts -- which makes Taylor's wild histrionics seem even more outlandish. Soon the viewer is left with only interior designs worthy of Architectural Digest and Taylor's wardrobe and hairdos to marvel at.

Witness to Apartheid is a disturbing documentary that sets out to examine South Africa's policies of forced racial separation and minority rule from a unique point of view: their effect upon children.

``Witness'' tells its story through the words and images of witnesses -- young, old, black, and white -- who talk mostly about police actions as methods of torture and repression. This viewer wanted to turn away from the frequent footage that shows injured children and illustrates the wounds graphically. ``Stitching up [without anesthetic] is used as a form of torture,'' alleges one doctor.

Bishop Desmond Tutu, interviewed in the program, frames the issue as follows: ``This is not a matter of civil rights; it is a matter of human rights.'' Bishop Tutu, himself a gentle man who now believes his gentle approach has not worked, voices doubts about the future of peaceful resistance. He underlines the difference between the civil-rights movement in the US, where the law was on the side of the movement, and the current battle in South Africa: ``Here we do not have the support of a constitution and the law. Here we have to dismantle the whole system.''

``Witness to Apartheid'' bolsters its message of systematic police brutality with images of ruthlessly injured children -- pictures that stick in the memory. But the documentary fails to uncover much that's new. And it doesn't really get below the surface to offer any alternative to violence. Its message could be summarized in the words of a young man who says: ``The black man will get freedom through the barrel of a gun . . . and no way else.''

Sunday night viewers who choose not to watch the aforementioned programs might want to look in on the alternative on NBC. That network is airing the 1983 movie ``Trading Places'' (9-11:30 p.m.), a wild comedy starring Eddie Murphy and Dan Aykroyd, which, amid the laughs, actually manages to include some insightful satire on contemporary American life.