Rescue brought terror, then relief

• At first, Michelle Knight says she thought rescuers were burglars


• She told police: "Please don't let me go. Please don't "


• Knight tells CNN her feelings about Ariel Castro's suicide


• The past year, she says, has been "overwhelming but amazing as hell"

(CNN) -- First, Michelle Knight heard pounding on the door. Then, there was silence.

A year later, she still remembers the dread she felt that day.

Rescuers were banging on the door after learning Knight and fellow captive Georgina "Gina" DeJesus were trapped inside. But Knight and DeJesus didn't know the police were coming.

"For me it was the most awesome day ever. But it was also terrifying at the same time, because me and Gina actually thought someone was breaking in," Knight told CNN's Anderson Cooper in an interview that aired Wednesday. "We laugh about it now."

Ariel Castro listens during the sentencing phase of his trial on August 1 in Cleveland alongside defense attorneys Craig Weintraub, left, and Jaye Schlachet. Castro held three women captive for years inside his Ohio home until their escape in May 2013. He pleaded guilty to 937 counts, including murder and kidnapping. On September 4, Castro was found dead inside his prison cell in Orient, Ohio.

Former captive Michelle Knight, center, talks with reporters on August 7 outside convicted kidnapper Ariel Castro's house. Knight was on hand as workers began tearing down the structure.

A crane demolishes the Cleveland house of Castro on August 7. Plans call for the house to be torn down and the lot cleared in a single day.

Here is a view of the house where Castro held the three women captive. He forfeited the house as part of a plea deal with prosecutors that took the death penalty off the table in exchange for a life sentence, plus 1,000 years in prison.

Michelle Knight speaks during the sentencing phase for Ariel Castro on August 1 in Cleveland. "I will live on," Knight said in her statement to Castro. "You will die a little every day."

Amanda Berry vanished a few blocks from her Cleveland home on April 21, 2003. She was 16. She spoke in a video released on YouTube on July 8, thanking people for support and privacy. Berry, Gina DeJesus and Michelle Knight escaped from a Cleveland home on May 6, 2013, after being held captive for nearly a decade.

Georgina "Gina" DeJesus was last seen in Cleveland on April 2, 2004, on her way home from school. She was 14 when she went missing.

Knight was last seen on August 22, 2002, when she was 21.

FBI agents and other law enforcement officers stand outside Castro's home in Cleveland on May 9, 2013.

Castro hangs his head while talking with his public defender, Kathleen DeMetz, during his arraignment on May 9, 2013.

Ariel Castro was charged on May 8, 2013, with kidnapping the three women.

Investigators remove evidence from the house on Seymour Avenue in Cleveland where the three women were held.

An FBI forensics team meets outside the house where three women were held as they investigate the property.

Cleveland Deputy Chief of Police Ed Tomba, center, speaks at a news conference to address details of the developments.

FBI agents remove evidence from the house May 7, 2013.

A police officer stands in front of the broken front door of the house on May 7, 2013, where the kidnapped women escaped.

Neighbor Charles Ramsey talks to media as people congratulate him on helping the kidnapped women escape on May 6, 2013. He helped knock down the door after he heard screaming inside.

Kidnapped teens found decade later

Kidnapped teens found decade later

Kidnapped teens found decade later

Kidnapped teens found decade later

Photos: Kidnapped teens found decade later

Photos: Kidnapped teens found decade later

Photos: Kidnapped teens found decade later

Photos: Kidnapped teens found decade later

Kidnapped teens found decade later

Kidnapped teens found decade later

Kidnapped teens found decade later

Kidnapped teens found decade later

Kidnapped teens found decade later

Kidnapped teens found decade later

Kidnapped teens found decade later

Kidnapped teens found decade later

Kidnapped teens found decade later

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Photos: Kidnapped teens rescued

Knight: 'I was the punching bag'

Michelle Knight on Amanda Berry's baby

Michelle Knight: I didn't want to get shot

But at the time, it was anything but funny. The two women huddled in their boarded-up bedroom, afraid burglars were coming for them, Knight said.

That terror turned to relief, Knight said, when she caught a glimpse of a police badge and heard a police radio.

It wasn't long before she jumped into the police officer's arms.

"I ran right into her arms," Knight recalled, "and I literally choked her. ... (and) I said, 'Please don't let me go. Please don't put me down.'"

At 32 years old, Knight walked out the front door of 2207 Seymour Avenue for the very first and last time.

How Castro lured her to the house

Knight recalls being Castro's 'punching bag'

Confrontation in court

For 11 years, Knight was brutally raped and tortured in Ariel Castro's "house of horrors."

Rescuers freed her, along with fellow captives DeJesus and Amanda Berry, a year ago from the Cleveland home, drawing national attention to the horrific case.

Knight was rushed to a hospital, where she was treated for a long list of health issues due to the years of beatings and neglect.

Although she was free, she was also alone. With no family to speak of, friends or home to go to, she took refuge at an assisted living facility outside Cleveland, where she prepared to face her captor in court.

"After 11 years, I am finally being heard, and it's liberating," she said in a powerful statement at Castro's sentencing describing the abuse she endured.

"You took 11 years of my life away, and I have got it back. I spent 11 years in hell, and now your hell is just beginning," she told Castro.

Knight told CNN she was determined to speak out.

"It was important to me to express how I felt about what he did and how he did it and let the judge know that he needed to be punished," she said.

Hope for the future

Michelle Knight: He said he had puppies

Michelle Knight: You're powerless

One year later, Knight is in a very different place. While Berry and DeJesus have largely stayed out of the public eye, Knight has done the opposite -- appearing at public events and writing a book, "Finding Me," in hopes that her experiences will help people know they can survive anything.

Castro, the daily devil in these three women's lives for so long, is now out of the picture.

He killed himself in prison last September, just a month into serving his prison sentence of life plus 1,000 years.

"I understand why he did it," Knight said. "He couldn't face what he did with his head held high. He had to face it like a coward, 'cause he was ashamed and embarrassed of what he done. And he didn't want what he did to us to happen to him."

Now, armed with friends and a good support system, Knight said she's giving a voice to other people who are missing, like she once was.

"I was considered a forgotten one," she said. "That's a reason why I made a poem and said that all the people that are out there, they're not forgotten in my eyes. Never."

And she's focused on starting over.

The past year, she said, has been "overwhelming but amazing as hell."

She has changed her name to Lily, after her favorite flower. She's back in school with the hope of opening her own restaurant.

And she's planning to get a new tattoo with a message of survival: "God gave us this chosen life because He knew we could handle it."

After what she's been through, Knight said there's nothing she can't handle.

Berry's baby delivered by another captive

Michelle Knight recounts her experience to Dr. Phil

CNN's Greg Botelho and Dana Ford contributed to this report.

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