The "courtroom" is cold. Plaster is chipping from the walls, exposing brick. There hangs a portrait of party chief Gustav Husak. The scene is Czechoslovakia, Oct. 22, 1979, and the biggest show trial in post-Stalin Eastern Europe is about to begin -- again.

Unfortunately, the real defendants could not be present this time. They are in jail now, serving long terms for signing a manifesto three years ago called Charter 77. It demanded that the Prague government abide by the guarantees of freedom of expression in the Czech constitution and honor the human-rights provisions of the 1975 Helsinki agreement. More than 1,000 persons signed, but six were singled out for trial as a warning to the others.

Now the trial has been replayed in Munich, as "The Charter 77 Trial," with some of Europe's best-known artists substituting for the relatively unknown members of the original cast.

There are Simone Signoret, grande dame of the French cinema, French director Ariane Mnouchkine and exiled Czech playwright Pavel Kohout playing the defendants. Among the attorneys are German movie director Volker Schloendorff and Czech-born dramatist Tom Stoppard, who now lives in England. In the judge's chair is German actor Hans Christian Blech.

The replay was recorded and shown on German television recently, and will be beamed to Czechoslovakia. It already has been staged in Paris, and will be performed this week in Vienna -- all of which must be frustrating to the Czech government, which went to [TEXT OMITTED FROM SOURCE] two of them would be because they lived up in the country. I got a man to drive me in the car, up a country severe measures to keep the trial out of public view.

Czech authorities never actually closed the proceeding. They simply assigned the trial to the smallest courtroom in Prague city hall, a room thar can hold only 18 spectators. Only the closest relatives of the defendants could find room. All others -- including foreign journalists, Western diplomats and members of Amnesty International -- were turned away for lack of space.

One of those denied a seat was French stage director Patrice Chereau, an unconventional and energetic personality and guiding spirit of a human-rights group called the Association Internationale pour la Defense des Artistes (AIDA).

Chereau waited in a nearby cafe where those who witnessed the trial stopped after it was over. Several had secretly taken notes, and Chereau returned to France with an unofficial transcript of the proceedings.

"This is not a theater performance," the French director declares in a prologue to his production. "We want to be witnesses tonight. We will be speaking for those who are forced to be silent."

There have been aspersions in the press that the stars are taking personal advantage of a celebrated trial. Chereau has rejected these claims by citing other protest actions taken by AIDA against human rights violations in Argentina, Colombia, Chile, the Soviet Union, Iran and South Africa. iAlso, the performers received no pay for their roles in the Charter 77 replay.

The retrial was staged not in a theater, but in an old streetcar depot in a blue-collar neighborhood, after the fashion of Soviet revolutionary art. About 900 persons watched from wooden bleachers that rose above both sides of the stage. The sense of being witness to a circus seemed intended.

Each of the accused steps forward to offer a defense. The judge alternately interrupts, badgers, mocks, interrogates and accuses. Isn't it true, he asserts, that Charter 77 is a conspirative organization with secret foreign contracts and CIA funding? Not so, insist the accused. Theirs is a public group, self-financed, formed spontaneously, with no intention of undermining the state.

The resolve of the defendants seems to be thickened by the stirrings of the court. It reaches defiance in a statement red by Simone Signoret, who plays TV journalist Otta Bednarova. After five months in jail, she says, this is the first occasion she has had to see more than three people. sShe does not believe in the trial under way, she declares. She does not wish to stay. She does not want to be manipulated.

The judge orders her to answer his questions. She refuses and sits down.

The defense attorneys are hardly much help. One is absurdly comical in the way he lectures his own client in court.

"He may be knowledgeable about mathematics," says the lawyer for Vaclav Benda, a computer designer who was subsequently forced by the state to work as a stoker, "but he does have some strange ideas about Czech laws. I cannot resist the reproach, Shoemaker stick to your trade. This is mine. I ask for a plea of not guilty."

The farce draws laughter from the audience. But it is funny only from the secure distance of the Munich depot.

A closing statement by Pavel Kohout delivers the drama's most powerful message. Kohout, a playwright who himself last year was denied permission to reenter Czechoslovakia after a year in Austria and was later stripped of his Czech citizenship, portrays the dramatist Vaclav Havel, the best known in the West of the defendants Havel's "The Memorandum" was acclaimed "best foreign play" in 1968.

To win time from the judge, Kohout adopts the simple-minded manner of the Czech folk character Schwejk, a fictitious poor soldier figure in Czech stories who often feigns stupidity and subservience to cunningly win his way.

Kohout describes in court how he had been visited two months earlier by two people who offered him a chance to emigrate to the United States. He decided to remian, he says, which should be proof that he does not oppose his country. It cannot recognize the difference between criticism and offense.

Switching suddenly from German to Czech, Kohout speaks these last words in his native language to be sure that whoever catches the broadcast across the border will understand.

At the close, the prison sentences are read: Havel, 43, playwright, 4 1/2 years; Brenda, 33, computer designer, four years; Bednarova, 54 TV journalist, three years; Peter Uhl, 38, economist, five years; Jirl Dienstiber, 42, broadcast journalists, three years; Dana Nemcova, 45, psychologist, mother of seven, suspended sentence.

When originally ordered on Oct. 23 of last year, these sentences brought a wave of condemnations from the West, ranging from Pope Paul II to the French Communist Party. They also seemed to have had an effect on the Charter 77 movement in Czechoslovakia opposite from that intended by the Prague regime. Earlier this month the dissidents issued a fresh declaration reflecting a renewed sense of solidarity.

There is an old Czech parable that was written on the wall of the Munich depot where the reenactment was staged. It says:

"Before the law a doorkeeper is standing. A man from the countryside asks him if he may enter into the law. But the doorkeeper says, 'Not now.' The man asks whether he might be allowed to enter later. 'It is possible,' says the doorkeeper, 'but not now.'"