MOSCOW - On Oct. 23, as always, the second act of the Broadway-style musical Nord-Ost opened with a line of pilots in Soviet-era uniforms tap-dancing across the stage.

As always, Yekaterina Moreva was in the orchestra pit. She touched her bow to the strings of her violin, ready to play a military march for the hero, who was about to stride from the metal hangar doors that served as a curtain.

But instead of music, a tragedy began.

Moreva heard gunfire before she could play a note.

Instead of the play's hero, a man appeared on stage wearing camouflage and a black ski mask and carrying a Kalashnikov. Instead of the sounds of the orchestra, what the 700 or so people in the audience in the main theater of the Palace of Culture heard was the sound of bullets being fired into the ceiling.

The audience, musicians and cast members would be the heroes and the victims of a hostage crisis that would last 57 hours. It would bring the ruthless fighting of the Chechen war to within three miles of the Kremlin, and its effects would be felt throughout Russia.

No previous show performed on that stage could match the tragedy that was about to unfold. Politicians would plead with the 40 or so guerrillas in the theater for the hostages' release. Parents of hostages would plead for the Kremlin to capitulate to the guerrillas' demands by withdrawing troops from Chechnya. Authorities would try to end the hostage-taking without killing everyone in the theater.

President Vladimir V. Putin would be praised for his decisive action and criticized for his ruthlessness in ending the crisis. Chechens throughout Russia would brace for a brutal crackdown. Some Russians would wonder whether the event would expand the power of security agencies.

None of that immediately concerned Yekaterina Moreva - Katya to her friends. The 40-year-old musician responded as any rational person might to the gunman on stage.

Clutching her violin, she ran.

She hesitated only when she reached a door leading to the basement. She wondered whether her husband, Igor Morev, had run, too. She didn't see him there jostling with the other musicians. So she froze.

Igor, a 39-year-old violinist with sad blue eyes, still sat in the orchestra pit, staring up at the gunman on stage. When Igor refused to climb out of the pit, the gunman said, "I am going to kill you now."

"I am going to leave," Igor said and slowly walked toward the exit to join Katya. All the musicians who could fit locked themselves in the women's dressing room, the place where they spent intermissions drinking tea.

For each performance, they earned a mere 470 rubles, about $15 - half the price of the best tickets for the show. Now, in the dressing room, they followed events in the theater on the screen of a closed-circuit TV.

"Those are Chechens up there," someone said in the dressing room. "Do you hear their accents?"

It was about 9:15 p.m., and Katya, now with plenty of time to think, realized she had ignored an early sign of trouble. During intermission, she had used a pay phone by the stage entrance and seen a guard in camouflage. He wasn't a guard, she understood now, but a guerrilla preparing for the raid.

Other than wait, all the musicians could do was use their cell phones to call relatives and police. Family members said they were watching the events on TV, and authorities said help was on the way.

After 10 p.m., two guerrillas rattled the knob of the dressing room's locked door. "If you don't unlock the door," a voice said, "we'll shoot the door apart."

The musicians opened the door.

Tracking the guerrillas

Also about 10 p.m., police, military forces and the Federal Security Service set up a headquarters in War Veterans' Hospital No. 1 across the street from the theater. In the Kremlin, Putin was briefed about events. All over the city, cell phone users saw an exclamation point appear on the screens of their phones - a sign, according to the Moscow Times, that encryption systems had been turned off to allow the security service, known as the FSB, to intercept calls.

The eavesdropping apparently helped authorities identify and track the guerrillas in the theater. There were at least 44 hostage-takers, 18 of them women, all of whom evaded the city's frequent, random police checks and arrived at the theater in minibuses and jeeps.

All the men wore camouflage; all the women dressed head-to-toe in black dresses and veils. Each woman wore a belt holding plastic explosives studded with ball bearings and was armed with a pistol and grenade.

Movsar Barayev, a 25-year Chechen warlord, was their leader. His clan had a reputation for violence. More than once, the Russian military had reported his death, most recently 10 days before the theater raid.

Barayev made only one demand: that Russia withdraw its troops from Chechnya. On a Web site sympathetic to the Chechens, the guerrillas called themselves smertniki, a Russian word for someone ready to die for a cause.

Some of the hostage-takers were teen-agers who seemed as surprised as their hostages by the seriousness of their situation. A few of the older men remained masked and threatened to beat or shoot their captives.

Soon it was past midnight, and the guerrillas had released 20 children from the theater. Katya, Igor and the other musicians were placed in the front rows, facing the stage. Igor sat to Katya's right; on her left was Volodya Zhulyov, a 43-year-old cellist.

A female guerrilla sitting near Igor said she had a 1-year-old daughter and bitterly described the privations of the Chechen war. "Our children cannot even go to school," she said. "And you here in Moscow can go to such performances."

When Igor told her how little musicians earned for their work, she seemed surprised. "Four hundred seventy rubles?" she said. "I wouldn't get up from the sofa for that."

Barayev talked on a cell phone as he walked toward the stage. When his call was over, he addressed his hostages in a voice many had to strain to hear.

"If they are not going to meet our demands," he said of the Russian authorities, "we will start the second part of our operation. We will start to throw your heads out into the street so they will understand we are not joking."

In the early hours of Oct. 24, a British man in his 60s began to sob. "He kept asking what was going on," remembered Georgi Vasilyev, who was the producer of Nord-Ost and one of the hostages. "He was there with his wife and son. But strange as it seems, he was released. But his wife and son were not. What is stranger, he left."

Shortly before 4 a.m., a 26-year-old perfume store clerk, Olga Romanova, sneaked past police lines and into the theater. She hoped to negotiate a peaceful end to the standoff, relatives said later. The Chechens suspected she was sent by the FSB. They took her into the lobby and shot her in the chest. Her body was left where it fell.

It was a long night. "We were sitting there trying to make jokes because it was necessary to keep up our spirits," Katya said. "Of course, we knew from the beginning that we were not going to withdraw our troops from Chechnya."

Medical help

Dawn broke. Light leaked into the theater. The captives catnapped in their seats, read books or filled in crossword puzzles. Katya read prayers. Igor, who had only recently started going to church, flipped open his wife's Bible, and he, too, began reading.

Dr. Leonid M. Roshal, director of a Moscow hospital, had watched the drama unfold on television. He went to the theater, and the guerrillas allowed him to come inside. Finding a few physicians among the hostages, Roshal put each one in charge of a section of the theater.

One boy had pneumonia. A man lay on the floor with peritonitis, a life-threatening inflammation of the lining of the abdominal cavity. Roshal pleaded that the man be allowed to leave.

"If he dies," one of the guerrillas shrugged, "he dies."

Another guerrilla had been wounded in the arm. Roshal led him to the men's room and began to clean the wound - only to be interrupted by gunfire and explosions from the women's toilet next door.

Two 18-year-old women had jumped out of the window. Guerrillas rushed in and fired two grenades. Russian security forces were firing back.

Dragging the physician back into the hallway, the guerrillas accused him of helping the women escape. He managed to calm the gunmen. One of them had been wounded in the leg by a ricocheting bullet. As Roshal bandaged him, the gunman muttered that if he had been seriously hurt, he would have hobbled to the theater and started shooting hostages.

In the theater, guerrillas were running up and down the aisles. Katya and scores of other hostages ducked under chairs.

"Anyone who hides under a chair, we will throw grenades at them!" one of the Chechens shouted from the stage.

The guerrillas cut off use of the bathroom and forced hostages to use the orchestra pit as a toilet. They kept making threats. At one point, the gunmen promised to shoot 10 people an hour if their demands weren't met.

Day again became night. When Barayev walked back onto the stage, Katya judged that he seemed gravely disappointed. Barayev did not say so, but Katya believed he had realized that the Kremlin would not negotiate. He would have known he was doomed. Some of the Chechen women were crying. "They didn't want to die," Katya said.

Most of the hostages spent another sleepless night sitting in the theater's plush red seats. Zhulyov, the cellist, managed to doze. Waking, he would nudge Katya and ask: "What do you think? Will everything be all right?"

Tensions rise

By dawn Oct. 25, the Chechens had lost their confidence. The woman guarding Katya and Igor said she hoped to soon be on a plane returning to Chechnya, with a few hostages as insurance.

Other guerrillas told the hostages to write a letter to Putin asking him to end the Chechen war or to ask relatives to stage an anti-war demonstration in front of the Kremlim. At 8 a.m., the guerrillas announced that they were ready to negotiate the release of their foreign hostages. A parade of ambassadors came to the theater, but the promises came to nothing.

About this time, according to the Russian news media, members of an anti-terrorist squad took up positions in the building's basement and upper floors. Later in the morning, radio and TV stations reported that a pipe had burst and flooded the building, a report that may been used to explain noise made by the anti-terrorist squad.

Barayev continued talking to reporters by cell phone. At noon came word that he was threatening to begin shooting hostages by 10 p.m. if his demands weren't met. He postponed his deadline until 6 a.m. Oct. 26, then until noon.

He let Roshal, the physician, leave with eight children, but 20 others remained. Roshal returned with cases of fruit drinks. A gunman examined Roshal's stethoscope, concluded it was really a camera and denounced him as a spy. With some effort, Roshal convinced him of his good intentions.

More and more, the Chechens feared what the Russians would do. Gunmen began checking the ventilation ducts out of fear that commandos were crawling through them. The Chechens warned their captives that they would be shot at dawn. As the evening wore on, the guerrillas grew more sullen and reluctant to talk.

"They many times told me: 'We will die, we will die. We have many bombs,'" Roshal said. "And I thought, if you have so many bombs, and you are really ready to die, why talk about it so much?"

A series of negotiators came and went from the theater, none of them finding success. About midnight, a man arrived claiming to be a distraught father worried about an 18-year-old son. The guerrillas beat the man until his head was bloodied and dragged into him into the theater. No son could be found.

"You see?" a gunman shouted from the stage. "This man is a provocateur!"

The man was dragged into the lobby and shot.

Few in the audience seemed to care.

A bizarre, critical event occurred after midnight, when a distraught man stood and shouted, "Dear mother, I don't know what to do!" He threw an empty water bottle at the Chechens.

One of the gunmen fired at the Russian, but the bullet missed its target, passed through the chest of a second hostage and then struck a third in the head.

And then the Chechens did something unexpected. Despite having executed several people, they telephoned authorities for medical help. An opportunity for both sides was about to be missed. Having heard gunshots, Russian officials apparently concluded that they were about to run out of time. Instead of sending help, they set an assault in motion.

Gas began entering the theater.

Katya recalled a guerrilla waving his gun on stage and shouting, "Turn off the ventilation!"

Some of the gunmen tried to run. Most of the hostages, and the gunmen, succumbed to the gas. Katya was half-asleep when her husband, Igor, nudged her.

"Katya, I think it is gas coming," he said. "Wet your handkerchief and breathe through it." He had a wet handkerchief over his nose.

Except for a faint sweet taste, the gas was nearly undetectable. "There was this fog in my brain," Katya said. "I looked at Igor, and he was already sleeping. And I thought, we will wake up, and we will be together again."

Theater is stormed

At 6:30 a.m. Oct. 26, about 100 troops stormed the theater. They came through the front doors, up through the basement and broke down a wall from a neighboring club.

One hostage, Olga Rudapova, later told Russian television that she managed to stay awake and saw two soldiers run into the theater. They approached an unconscious female guerrilla, a bomb strapped to her waist. They briefly deliberated. Then one of the soldiers shot her. In all, 41 Chechens were shot to death, including Barayev.

Katya Moreva slept through most of it. What she recalls is walking unsteadily through the theater parking lot toward a city bus. A woman was holding onto her arm. "It was as if there were hammers striking in my head," she said. She gripped the armrest of the bus as it careered through the dark, wet streets.

Hundreds of other hostages were carried out by rescue workers and soldiers and laid on the sidewalk. On television, rescue workers could be seen giving some of them injections of Naloxone, the antidote to the anesthetic gas. For four days, the Kremlin refused to say what kind of gas it had used. Finally, Health Minister Yuri L. Shevchenko disclosed that it was a potent compound of synthetic opiates related to Fentanyl

Mikhail Margelov, chairman of the State Duma's Foreign Affairs Committee, told BBC Television that some people received injections of Naloxone, some received two injections and some didn't receive any injections at all before arriving at the hospital.

All but two of the 120 hostages who died were killed by effects from the gas.

The bus took Katya to Hospital No. 13. She walked to a third-floor ward: The elevator wasn't working. She was given a shot and told not to go to sleep. She lay there on her side, nauseated. She was very thirsty. She received two more shots, one a heart stimulant and the other for her terrible nausea. She could hardly hold her head up, but other women in the ward worked hard to help keep her awake. One even danced for her.

Katya stayed awake until noon. She was told that Igor was in the same hospital, but she couldn't see him - not yet. She slept. When she woke, she asked a doctor about her husband. She was told he wasn't there.

Igor's friends and family organized a desperate search. The next day Katya's eldest son telephoned. He had recognized a photo in a city morgue.

"I could not cry," Katya said.

Of the 32 members of the orchestra, eight died, including Igor. Zhulyov, the cellist, died, too. So did a second cellist, two clarinetists, a flutist and the oboe player. "They were all very handsome young people," Katya said.

But her husband was someone extraordinary, she said, rare and fragile. "He said, if he hadn't met me, he would have died very young," she said. "His soul was sad. His soul always cried."

He did not understand the war in Chechnya, or any war, his widow said. "Igor had a hard time going through all this suffering. Not only in this situation, but for all the atrocities going on in the world. He was someone who had never said a bad word to anybody."

He was buried Friday.

She remembers watching the nervous guerrillas, the last night of the siege.

"Actually, all of us were hostages," she said. "The Chechens, and the Russians. If they want to live separately from us, let them live separately." She knew that much of Chechnya had been destroyed, families slain.

"I am not going to curse them and take revenge because they are already cursed," she said. "And God has already punished them."