Alfredo and Marian Lopez were asleep when the first thundering blast jolted them awake. Moments later, a second boom, much louder than the first, shook the couple's bed in their sixth-floor Surfside, Florida apartment.

Alfredo, 61, rushed to wake his 24-year-old son Michael, urging him to get dressed quickly. Then he ran to the window.

"All I could see was just white dust, very thick," he said. "I could barely see the balcony railing."

The lights cut out and the emergency alarm sounded, warning residents of Champlain Towers South to evacuate. Alfredo Lopez thought about putting on sneakers, but his hands were shaking so badly from fear he knew he couldn't tie the laces. He settled on sandals with straps.

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Marian Lopez, 67 was disoriented. She fumbled for shoes as her husband urged her to move quickly.

For two decades, the family has lived on the street side of the condo tower. Alfredo used to joke to his wife she'd have to bury him there. On June 24, it very nearly happened.

When he opened the front door that night, half of the building was gone. A jagged five-foot chunk of flooring barely left enough room to escape.

"There was no hallway, no ceiling, no apartments, no walls, nothing."

He remembered being frozen in terror.

"I was petrified. I really thought, ‘This is it. We are going to die.'"

Sometimes, the line between life and death in such a calamity can be as seemingly random as whether an apartment had an ocean or street view. While 126 residents, mostly from the ocean-view units, are among the missing nine days later, many others barely escaped. 

With the elevator collapsed, the survivors descended the cracked stairwell that had separated from the wall, along the way helping neighbors they met for the first time and others they'd known for years. They were all "joined through this tragedy for forever now," said resident Albert Aguero, who helped an 88-year-old stranger to safety.

While their escape felt agonizingly long, it unfolded in mere minutes. In those perilous moments, before the world knew of the more than the 22 people who perished and the many missing, they were fighting to survive.

"When I opened the staircase door and half the staircase was missing, at that point I know we’re racing against time to all get out as a family," Aguero said.

Down on the first floor, recent college graduate Gabriel Nir had just finished a late-night workout and was in his kitchen cooking salmon. The rest of the family would normally be asleep, but his 15-year-old sister had just returned from babysitting and was in the shower, his dad was out of town and his mom had just come home from an event.

They all heard the first ominous rumble. They knew the building was undergoing construction and had been irritated by the incessant noise, but this felt different – more thunderous.

Sara Nir, Gabriel's mother, ran to the lobby, asking the security guard if she’d seen anything.

Back in the kitchen, concrete dust billowed into their apartment from the patio windows near the pool. The ground was shaking as 25-year-old Gabriel ran to the bathroom.

"We have to go now!" he screamed to his sister. They ran to the lobby, where their mother urged the security guard to call 911. The guard was too rattled to remember the address, so Gabriel phoned.

"Please hurry, please hurry," he begged the dispatcher.

Outside, he saw that the car deck had caved into the parking garage. Car alarms were blaring, emergency lights were flashing and water from ruptured pipes was rapidly filling the garage.

He ran back to the lobby, where the dust cloud was making it difficult to see. Residents from upstairs were running out the door screaming, many still in pajamas. One man pushed a baby stroller.

It was getting harder to breathe. The rumbling intensified, as Gabriel ushered his mom and sister into the street.

"Run, run!" he yelled.

Rocks and other debris pelted his head as he turned back. It would be a sight that would haunt him days later.

"I saw the building turning into a white dust," he said. "I heard people screaming."

His first instinct was to go back inside. "I have to make sure everyone's OK," he thought.

But it was too late.

Up on the 11th floor, Aguero stared in disbelief at the gaping holes in the elevator shaft.

Gabriel Nir, who lived on the first floor of the Champlain Towers South condo building that collapsed, poses for a portrait outside the hotel where he is now staying in Surfside, Fla., on Friday, July 2, 2021. He had just finished a late night workout and was in the kitchen cooking salmon. The rest of the family would normally be asleep, but his 15-year-old sister had just returned from babysitting and was in the shower, his dad was out of town and his mom had just come home from an event. They all heard the first thunderous rumble. They knew the building was undergoing construction and had been irritated by the incessant noise, but this felt different. (AP Photo/Gerald Herbert)

Gabriel Nir, who lived on the first floor of the Champlain Towers South condo building that collapsed, poses for a portrait outside the hotel where he is now staying in Surfside, Fla., on Friday, July 2, 2021. He had just finished a late night workout and was in the kitchen cooking salmon. The rest of the family would normally be asleep, but his 15-year-old sister had just returned from babysitting and was in the shower, his dad was out of town and his mom had just come home from an event. They all heard the first thunderous rumble. They knew the building was undergoing construction and had been irritated by the incessant noise, but this felt different. (AP Photo/Gerald Herbert)

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Half of the neighboring apartment was sheared off. The power was out. Aguero wondered if it had been struck by lightning. 

The fit 42-year-old former college athlete was vacationing from New Jersey with his wife Janette, 14-year-old daughter Athena and his 22-year-old son Justin Willis, a college baseball player.

His son thought a plane had crashed into the building. There was no time to talk as they rushed into the stairwell, wondering if could make it down 11 floors in time.

"There was no time to react. Just make your move," Aguero recalled.

Each time they made it down another level, they yelled out the floor number. It was a small victory, one floor closer to survival.

Moving as fast as they could, none looked back. Instead, they frequently called out to each other.

"Justin, are you still there?"

"Babe, are you OK?"

When they reached the fifth floor, Janette heard banging on the staircase. She wrenched open the frozen door and a few more terrified residents joined them on the stairs, including a young lady clutching an elderly woman.

She asked Aguero and his son to help the elderly woman, which they did. There were some cracks and gaps down the stairwell, but nothing unpassable.

Still, the pace was too much for the old woman.

"Don't worry about me. I’m 88. I've had a good life," she said, waving them on.

But Albert Aguero was determined. They were all going to make it out alive.

"You’re going to be fine," he reassured her. "We’re going to make sure you make it to 89."

On the ninth floor, Raysa Rodriguez and her neighbor Yadira Santos huddled in the hallway, along with Santos’ 10-year-old son Kai and their Maltese puppy. They’d already seen that the other half of the building was gone and assumed the stairwells were too.

She thought their only escape was to wait on a balcony until fire trucks arrived. In the chaos, her brother Fred called — he had rushed to the building and was standing outside. He kept repeating the same urgent warning.

"Get out of there, get out!" he pleaded.

There's no way out, the stairs are gone, she told him.

A firefighter grabbed Fred’s phone and uttered a chilling command. "You need to find a way out."

They decided to try the stairwell again. When they reached the eighth floor, they found 84-year-old Ada Lopez waiting with her walker. Santos had called to warn her.

Rodriguez rushed ahead to see if there was a way out as the others helped the elderly Lopez down the stairwell, bumping into the Aguero family and Albert Lopez's clan along the way.

But when Rodriguez reached the flooded parking garage, she turned around.

"I knew being electrocuted was a possibility," Rodriguez recalled.

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They rushed back upstairs to the second floor where someone had left their apartment doors open. Outside from the balcony, they flagged down rescue teams outside and a cherry picker brought them to safety.

Back in the stairwell, Alfredo Lopez was panicked. His wife in her panic had chosen to wear slippers to navigate their doomsday nightmare.

"What were you thinking?" he asked her, but he knew she really wasn't.

When they reached what could have been the second or third floor, Susana Alvarez from 1006 was knocking on the stairwell door, her 88-year-old neighbor Esther Gorfinkel beside her.

As Alvarez fled her apartment, she'd banged on her neighbors' doors one last time, using her cellphone flashlight in the darkness. From the wrecked side of the building, she heard screams.

"Help me, help me!" she heard a tearful woman shouting.

"There were people alive in there," Alvarez would say later.

The 62-year-old Alvarez had just had brought her beloved cat Mia to the building a week ago. In a few days, she was planning to move her mother into the condo. Alvarez is the only family member left to care for her mother, who has advanced Alzheimer's.

As she and Gorfinkel made their way down, Alvarez paused, thinking of Hilda Noriega on the sixth floor. She was like family. They'd spent many holidays together. Noriega and her mother had been best friends since their days in Cuba.

"Can I rescue her, can I go get her?" she thought frantically. "But I had already seen the building, so I kept going."

Gorfinkel complained they were moving too fast, her knee was giving her terrible pains. Without thinking, Lopez threw her over his shoulder and pressed on.

"The five of us became like a caravan," he said.

Alvarez couldn't stop talking about the cat.

"Forget about the cat," Lopez screamed in a moment of frustration. "We've got to get going."

When they got to the flooded garage, one car was on top of another, crushed by a giant slab of concrete.

Alvarez panicked. She also was wearing slippers. It was too high to climb the pile of rubble onto the pool deck. The Aguero family had just made it onto the pool deck ahead of them, with father and son hoisting Gorfinkel up to safety.

"I cannot make it," she thought. Her hands were covered with blood, but she had no scratches, and no idea where it came from.

In this Sunday, June 27, 2021 image from video, Alfredo Lopez talks about how his family escaped from the Champlain Towers South condo building in Surfside, Fla. Lopez and his wife, Marian, right, were asleep when the first thundering blast jolted them awake. Alfredo rushed to wake his 24-year-old son, Michael. When Alfredo opened the front door that night, half of the building was gone. A jagged five-foot chunk of flooring barely left enough room to escape. "There was no hallway, no ceiling, no apartments, no walls, nothing." The 61-year-old froze in terror, unable to move. "I was petrified. I really thought, ‘This is it. We are going to die’." (AP Photo/Stacey Plaisance)

In this Sunday, June 27, 2021 image from video, Alfredo Lopez talks about how his family escaped from the Champlain Towers South condo building in Surfside, Fla. Lopez and his wife, Marian, right, were asleep when the first thundering blast jolted them awake. Alfredo rushed to wake his 24-year-old son, Michael. When Alfredo opened the front door that night, half of the building was gone. A jagged five-foot chunk of flooring barely left enough room to escape. "There was no hallway, no ceiling, no apartments, no walls, nothing." The 61-year-old froze in terror, unable to move. "I was petrified. I really thought, ‘This is it. We are going to die’." (AP Photo/Stacey Plaisance)

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Days later, Gorfinkel called the Agueros to thank them for saving her life. Alvarez, too, is adamant she wouldn't have survived without the Lopez family.

"Thanks to him and his son, we were able to climb that rubble."

Days later, the Agueros, and the Nir and Lopez families, are safe. They embrace their children and siblings tighter, knowing many of their neighbors are gone.

For now, the survivors have no homes. Their possessions are gone. Clothes, computers, cars, even prescription medicine. It's inconvenient, they say, but it doesn't really matter. They are alive.

At night, they still hear the screams, and the terror comes rushing back.

"The first few days, I had horrible survivor's guilt," said Lopez, a deeply religious man.

Gabriel Nir finds it difficult to sleep. He tries to stay busy, to push away the what-ifs.

"It’s like a virus. it just never goes away," he said sadly. "I wish I could have done more ... These people that are missing, they aren't coming back."

His family is crammed into a nearby donated hotel room. His voice is still filled with adrenaline. Days later, he's talks as if on fast-forward, clipped and frantic. Like his escape.

Nir says his near-death experience has taught him something valuable.

"Check on your loved ones ... it's only one life," he said. "You don't know what's going to happen, today, tomorrow, the next hour."

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Alvarez, too, is filled with grief. Hilda Noriega, her mother's best friend, is among the dead.

She hasn’t been in a bed since that night, can’t bring herself to crawl under the covers. She sleeps in a chair instead.

"The people in the rubble, I could hear them. Some were yelling ‘help,'" she said.

"That will haunt me forever. I will never forget that."