It is hard to explain, but the Serbs are a funny people, with a sense of humor dark and illuminating. Jokes here are a self-inflicted wound. This probably does not come across on CNN.

In this deeply dysfunctional society, at this exact moment, a prankster like Bogoljub Arsenijevic can be a dangerous animal. Because he wants out of the cage.

Known to everyone here by his nickname in this neat little city by a river, "Maki" is a graying former hard rocker with a fondness for Deep Purple licks. He has a fifth-grade education.

He is also an avant-garde performance artist in highly politicized plays, as well as a painter of large frescoes for 14 Serbian Orthodox churches, murals alive with ecstatic religious imagery. He describes himself as a religious man. He is not much to look at, a 44-year-old grandfather with long frizzy hair, aged in that way that men and women in the Balkans age, from the smoke and drink, the sausage and bread. He has had five children by four different women.

For the last decade, Maki has been waging a one-man campaign in Valjevo against the regime of President Slobodan Milosevic.

A few years ago, when the former Federal Republic of Yugoslavia was cracking apart, in Slovenia, Macedonia, Croatia and Bosnia, he and his neighbors declared their own independent republic. They elected ministers and held press conferences.

He also erected in the courtyard of his worker's colony, a block of dreary communist-era apartments near a tool and munitions factory, an edifice of molded plaster. It was, as Maki describes it with some delicacy, "a very lifelike image of the human male organ."

It was eight feet tall.

He dedicated it to the president of Yugoslavia.

Mocking authoritarian regimes is always problematic. His sculpture wasn't subtle, but it was daring. Maki thought it was funny, but the authorities did not get the joke. A busload of riot police were dispatched to dismantle the object with a vengeance, and Maki was arrested. He served four months in jail.

But this was only a prelude to his latest act of defiance. Frustrated with the slowness of change and the failure of ordinary, cowed people to do something--anything--he and a circle of friends and allies formed the Civic Resistance of Valjevo. They plastered the city with posters announcing a rally for change in the town square.

On Monday, more than 4,000 people showed up. Branko Antonic, news editor of a local independent radio station, said it was the largest gathering ever seen in the town. There have been similar, smaller demonstrations, every night this week.

What was remarkable about the demonstration is that until now, most of the opposition to the Milosevic regime has come from political parties and their leaders. Maki and his friends reject all that.

"We thought we should hold a civilian rally. For people. By people. We see the opposition parties as incompetent and we wanted to do something more serious." This is Kristina Peric talking. She is young and intense and is found, after several phone calls, in a small garret in the old quarter of the city. She is now leading the daily rallies. Thirteen of her comrades were arrested and Maki went into hiding. Peric describes Maki as the most courageous person she has ever met.

The night of the first rally, Maki stood before the crowd--beside graffiti that read, in English, "Only God can judge us." He demanded that Milosevic and his wife, Mirjana Markovic, leader of a sister party to her husband's socialists, be arrested and face trial in Yugoslavia--not at The Hague, where Milosevic has been indicted as a war criminal. Maki also attacked the traditional opposition here, which does nothing, he said, "but organize rallies and marches and petitions, nothing that can really endanger the survival of the dictator."

And so hundreds of people stormed the city hall. The idea was to seize the local government offices, controlled by duly elected members of Milosevic's Socialist Party, and then to call for citizens in other cities to do the same. Their intention was clear: They wanted to spark a revolution.

In the melee that followed, several police were injured. Windows were smashed. The crowd was dispersed with batons. Maki disappeared the next morning.

For the next few days, Maki would pass along to Peric "communiques," which were read aloud to the dwindling crowds that keep appearing at the town square each night in Valjevo. On Thursday evening, a few hundred people gathered and listened to Peric read aloud from the state-run newspaper Politika. The people listened and laughed, as if they were getting a joke.

The state-run media in Belgrade have labeled Maki a drug addict, an unemployed bum, a criminal and troublemaker. He confesses to only the last charge. Sitting at an outdoor restaurant in Valjevo, my cellular phone rang. It was Maki.

"I apologize I cannot meet with you at present," he said. "But I am out of town."

He was, in fact, in Bosnia. When would he return to Valjevo? Very soon. Would he reappear in public? Yes, when a crowd of thousands could be assembled to protect him from the police. If arrested, he said, he faces 10 years in prison as an enemy of the state and instigator of civil unrest. What was his message? "My message is that I appeal to the world to understand us and to help us in any way. This is the moment we have been waiting for. If we didn't believe in ourselves and this movement, we would have nothing."

And then he hung up.

CAPTION: Bogoljub Arsenijevic greets anti-Milosevic demonstrators.

CAPTION: Protesters in Valjevo, Yugoslavia, try to storm city hall to demand the resignation of President Slobodan Milosevic.