They were living in hell, and Ariel Castro did all he could to make sure they'd never escape it.
He tied and chained them up, removed handles from doors and replaced them with padlocks. He rigged entrances to the house with makeshift alarms, threatened them with a gun and fed them only once a day.
He covered windows to keep them out of view and sunlight out of their rooms.
But Michelle Knight, Amanda Berry and Gina DeJesus focused on the light at the end of the long, dark tunnel.
They nurtured the faith that they would one day be free. They clung to each other. They persevered and emerged from years of hell to find new life.
In their rare public appearances since, people have expressed surprise over how intact and at times cheerful they appear after all they have been through.
Frank Ochberg, a pioneer in trauma research who testified in the case Thursday, lauded the three women's survival and coping skills as "marvelous, compelling examples of resilience."
Ochberg testified when Castro was sentenced to multiple lifetimes behind bars.
Resilience. It's that state of mind that allows people to survive natural disasters, wars, the loss of whole families, even torture, and keep on living and eventually, hopefully, thrive.
"It means bouncing back," says the American Psychological Association.
On Thursday, Knight took a brave step in that direction.
She endured Castro's torment the longest. It has been said that, of the three women, she has had the roughest recovery so far. The accounts of the abuse Castro doled out to her were some of the most shocking.
When he made her pregnant, he pounded her belly, the women have said, until she miscarried. He has steadily denied the accusation.
She bravely walked into a Cleveland, Ohio, courtroom Thursday to face her tormenter, cast off the shackles of 11 years of his torture and sexual abuse, and wish him a life in hell.
Castro kidnapped her in 2002, when she was 21. He tore her away from her little boy, who was age 2 at the time, for what felt like forever.
"Days never got shorter. Days turned into nights. Nights turned into days. Years turned into eternity," she sobbed.
As she read her prepared solemn sendoff to Castro, tears drenched her face, filling one handkerchief after the next.
But she kept on. She let him know that while he descended into the depths of life in prison, she would emerge from this.
"I spent 11 years in hell, and now your hell is just beginning. I will overcome all of this that happened. From this moment on, I will not let you define me or affect who I am."
Taking hold of the situation and defining it for oneself is an important part of resilience, psychologist Rebecca Bailey told CNN's Anderson Cooper Thursday.
Knight and the others are developing "an understanding that you can move forward past these events," she said. They need to, so they can let go.
Resilience is "ordinary"
The strength in the face of their suffering may make Berry, DeJesus and Knight seem exceptional. But most of us are capable of the same spirit, the APA says.
"Research has shown that resilience is ordinary, not extraordinary." It points as an example to the large number of Americans who lost loved ones in the September 11, 2001 terrorist attacks and how they rebuilt their lives.