"Jagged Edge" is a courtroom drama of the kind that was habitually called "taut," back in the days when "taut courtroom dramas" were cranked out like kielbasa. And while I'll readily accede to its tautness -- you could bounce a quarter off the screen -- it hardly seems worth the bother. Despite handsome performances by Glenn Close, Jeff Bridges and a good supporting cast, "Jagged Edge" isn't a movie -- it's a director's exercise.

The movie begins when a San Francisco socialite is murdered in high Manson style -- epithets scrawled in blood, and so forth. The prosecutor (Peter Coyote) suspects the husband, Jack (Bridges); the defense attorney, Teddy (Close), is a corporate lawyer who returns to trial work precisely because she believes Jack's innocent. But her investigator (Robert Loggia), whom she used to work with in the old days in the prosecutor's office, suspects Jack too.

Who did it? Jack? The prosecutor? The jealous friend? The tennis pro?

"Jagged Edge" moves along with a brisk pace -- in this director's exercise, I give Richard Marquand an A; the test of a whodunit is whether it keeps you guessing who did it, and "Jagged Edge" delivers. But if Marquand adds a slickness to this tired material, it doesn't really make it any less tired; the movie never makes any claims on you that Perry Mason reruns wouldn't satisfy.

Screen writer Joe Eszterhas' strategy is simply and elegantly managed: have the evidence come filtered through characters with mixed motives, so that the audience never knows whom to believe. The prosecutor, for example, is an unscrupulous striver, a political opponent of Jack's; Jack is himself a social climber and famous manipulator. And Teddy, of course, falls in love with Jack. No one's point of view is objective.

Close shows more grit in her performance here than there's been in the past. Bridges is such an ingratiating screen presence that you almost miss the subtle twists he's putting on his character, the way he lets you know that Jack is ingratiating by design.

The priceless Robert Loggia, shambling imperially, breathes life into a familiar character -- the lovable foulmouth. Coyote plays the prosecutor as a no-account Dracula; and Louis Giambalvo is a real find as Fabrizi, a roly-poly who seems to appear in Smellovision -- he carries his garlic with him.

All of which, I'm afraid, makes "Jagged Edge" seem like more fun than it is. There's still the whodunit structure to deal with (when the villain is finally unmasked, I kept hoping, a la "The Man With Two Brains," that it would be Merv Griffin). There's no surprise to the surprise ending, because the filmmakers, from the way they've arbitrarily scattered clues along the way, knew who the villain was all along -- the movie stinks of red herrings. And while there are fine performances there are also the obligatory "no comment" scene, in which the prosecutor is hounded by reporters; the obligatory handcuffs-clattering-on-the-desk close-up; the obligatory pounding bass piano octaves; the obligatory "murmur-murmur-murmur" in the courtroom. And I guess I should know this by now, but what exactly is "badgering the witness"?