Redgrave stars in Renee Richards story. Performance borders on genius but falls to the level of a stunt

Sometimes an actor's performance is so good that it manages to uplift a routine script. That's craftsmanship, or perhaps even artistic brilliance. But when a bravura performance serves mainly to call attention to itself as a bold act of showmanship, that's a mere stunt.

Vanessa Redgrave's portrayal of a transsexual in Second Serve: The Renee Richards Story (CBS, Tuesday, 9-11 p.m.) is the latter kind of performance. Miss Redgrave gives a fascinating impersonation that teeters on the edge of genius before settling at the level of a circus act.

Redgrave portrays the tennis-playing doctor as both a man (Dr. Richard Radley) and a woman (Dr. Richards), switching back and forth in a sometimes puzzling display of androgyny, to the detriment of what little story line there is.

The script, by Stephanie Liss and Gavin Lambert, is based on the book ``The Renee Richards Story,'' by Richards and John Ames. Directed sedately by Anthony Page, the drama focuses predictably and boringly on early childhood dress-up adventures as well as adult cross-dressing. Very few of the psychological complexities of transsexualism or the medical considerations involved in a sex-change operation are dealt with in any depth.

The distress that the change causes Renee's son is touched upon only lightly, as is Dr. Radley's relationship with his wife. Sadly there is more emphasis on Renee's tennis game and her civil rights as a formerly-male tennis player making the rounds on the women's tennis circuit.

``Second Serve'' offers viewers little useful information or insight. It is mostly a rather discreet excursion into voyeurism and exhibitionism. If it were not based on Dr. Richards's book, one would dismiss it as mere electronic sensationalism, timed for the commercially-important ``sweeps'' period, when ratings results are used as the basis for future advertising rates.

Redgrave, with the help of expert makeup technicians and voice-deepening trickery, manages to look, move, and sound amazingly like a man part of the time. Unfortunately she also, at times, resembles a female impersonator when she is supposed to be looking like Renee.

If all this sounds a bit confusing, it is. Redgrave's American accent is totally unconvincing. On the whole, the Redgrave performance is restrainedly meretricious, dazzlingly bold, but noteworthy mainly for its cheekiness.

``Second Serve'' adds up to a faintly distasteful case of exploitative sexism in television. I'm not sure, though, which sex should file the complaint.