In room 221 of the Warsaw courthouse, one of the most popular shows in town has been playing for the past month, a minor but significant subplot to Poland's larger political drama.

It is the corruption trial of Kazimierz Tyranski, whose position as director of an export-import company afforded considerable contact with the west and responsibility for large sums of hard currency. He is charged with accepting bribes from foreign companies and arranging shady business deals that netted him as much as $1 million.

The court case is extraordinary in that Tyranski, because of his close connections to powerful officials and his shrewdness, was once thought to be untouchable.

Although his arrest came more than a year ago -- long before last summer's labor upheaval and subsequent shakeups in Poland's leadership -- the timing of the trial is advantageous to the Communist Party's announced war on corruption, a war considered crucial to revive public confidence in authorities. One of the more mysterious elements to the public proceedings, however, is the absence of specific reference in the court investigation or in testimony to the possible involvement of Tyranski's senior patrons in the party or government. It is as if he operated in a political vacuum.

"Where were Tyranski's superiors, where were the bodies of control or even colleagues who could have opposed his decisions, which they now describe as wrong? Where was the Ministry of Foreign Trade [which had oversight responsibility for Tyranski's company, Minex,] and its management?" asked Wanda Falkowska writing in the respected Polish weekly "Polityka."

According to the indictment, Tyranski received $460,000 from an Austrian company and $250,000 from a Swedish concern in return for directing business their way.

In addition, he is accused of robbing Minex of 473,000 West German marks and $311,000 by taking advantage of special discounts offered Minex by foreign firms and funneling them to Western European bank accounts left at his personal disposal.

Further, the prosecution charges Tyranski paid $6,000 to bribe the director of a Warsaw housing cooperative to get an apartment for his daughter.

The sums Tyranski is accused of receiving sound like fairy-tale amounts to average Poles. But more important to the state than the money involved are the prejudiced business decisions on major building and trading projects that were allegedly made as a result of Tyranski's tendency to play favorites. t

"His decisions concerning the choice of trade and partners and the terms of the deals made proved to be highly detrimental to the country's economy," reported the government-run Polish Pres Agency.

The scene in the crowded courtroom is bleak. At the front, on a raised platform, sit three black-robed judges in high-backed red chairs. On a long bench stretching before them are spread the 24 volumes of evidence in the case.

The prosecutor sits at one end of the bench. He appears to be an expert, witty interrogator whose confident, often sarcastic style implies he knows his evidence against the defendant is convincing.

Along the side of the courtroom, in a row of wooden benches, Tyranski, 57, sits flanked by two uniformed guards. He is balding, and his broad forehead rounds out a chubby face that conveys good-naturedness and the air almost of someone who somehow stumbled into an unfortunate affair, though few believe Tyranski stumbled unknowingly.

Also in the defendant's dock are Tyranski's wife, Teresa, and Adam Kuczynski, the Polish representative for a Swedish firm that had extensive dealings with Minex. Both have been charged with relatively minor misdeeds.

A wide assortment of witnesses has stepped forward to face the judges' bench from the small podium in the center of the courtroom. The list seems to include everyone who knows something about how Tyranski allegedly operated, from company chauffeurs and assistant managers to Tyranski's physician and a Polish woman familiar with Tyranski's London mistress.

Tyranski has declined to say much in open court in his own defense. In his one statement he said the practices he has been accused of were in existence before he became managing director o Minex in 1964. He denied having robbed the company, asserting that the money in his accounts was to be used to finance company activities. He has returned much of the money.

In further testimony, he described his activities as essentially beneficial to the company and emphasized his accomplishments as director.

In fact, during Tyranski's 15-year reign, Minex grew. The 1970s generally marked a boom period for Poland's foreign trade as a result of former party chief Edward Gierek's heavy borrowing from the West and investments in production. Minex deals in the import and export of Polish building materials, glass, ceramics and fireproof materials.

The tale of Tyranski's alleged wrongdoing, as described in court, begins in 1968 when he met Heinz Korzill, the owner of a small Austrian trading company. They became friends quickly; and Tyranski, according to evidence presented, subsequently spread word in Austria that trade with Poland should go through Korzill, who eventually monopolized Polish porcelain and glass exports to Austria and the Near East.

Their dealings also allegedly involved the reexport of Polish cement for a profit, and when the final reckoning between the two came in 1978, Korzill said he had spent $60,000 already on Tyranski and deposited an additional $400,000 into a Swiss bank account for him.

Other stories involve two Swedes, and alleged transfers of hundreds of thousands of dollars.

Tyranski did have a generous side. He reportedly purchased several cars and office equipment for the company using the funds he acquired, saying these items were gifts from foreign partners. The presents were said to raise the prestige and effectiveness of Minex.

Tyranski himself lived well. On a yearly salary equivalent to $6,000, he owned a home in the luxurious Konstancin area outside Warsaw valued at $150,000 and an apartment in Warsaw valued at $67,000. He took holidays in the Canary Islands and Majorca.

But for all the exposure of Tyranski's allegedly corrupt dealings, a sense of only partial justice being done hangs over the trial. "In fishing terms," said one Polish journalist, "Tyranski is only a tuna. The sharks haven't been caught."