Editor's note: "Piers Morgan Tonight" airs at 9 p.m. ET
(CNN) -- The three men spent 18 years behind bars for a brutal crime they said they did not commit. Locked away for life -- with one of them sentenced to death -- the men thought they would never experience freedom again.
They had been imprisoned for the brutal 1993 murders of three young boys in West Memphis, Arkansas. Evidence against the men was circumstantial, however, and doubts grew over the years about their guilt.
Finally, nearly two decades after the crime, the men were allowed to walk free last month, the result of a complicated plea agreement requiring them to plead guilty even while declaring their innocence.
The men came to be known as the West Memphis Three. Two of them spoke to CNN's Piers Morgan in an interview that aired Thursday -- their first sit-down interview since their release.
"I hadn't seen daylight in almost a decade. I hadn't been exposed to sunlight ... for almost 10 years," Damien Echols told Morgan about his life on death row, where he lived in isolation in a concrete cell, his food passed to him through a slot in a solid steel door.
"The only thing you can do to maintain your sanity is to not think about the case and not think about what's happening to you," Echols said.
"You have to create your own world in there or you'll go insane from that stuff."
Echols still squints in bright light, the result of living for years in a dimly lit cell. When he left prison and saw daylight for the first time in a decade, Echols said, "it was like having a spotlight turned right in your face. It was extremely bright."
Echols' friend and co-accused, Jason Baldwin, said he spent the first few years of incarceration being beaten up by fellow inmates, who targeted a man they thought was a child-killer.
He said he suffered a shattered skull and broken collar bone, had teeth knocked out, and was left with scars on his face.
"But as the years progressed and people got to know me, and as the documentaries (about the men's plight) came out and stuff, the curses turned into prayers," Baldwin said. "Those fights turned into hugs."
Baldwin, Echols, and a third man -- Jesse Misskelley, who declined to take part in the interview -- were imprisoned for the slayings of second-graders Steven Branch, Christopher Byers, and Michael Moore.
The boys' mutilated bodies were left in a ditch, hogtied with their own shoelaces. Prosecutors argued that the defendants -- teenagers at the time -- were driven by satanic ritual and that Echols had been the ringleader.
Echols and Baldwin said that at the time, they were targeted for being different from the rest of their peers in the small town where they lived. They read different books, wore different clothes, and had different haircuts.
"The evidence against us was our personal preferences in music," Baldwin said. "I remember at one point during the trial, they lifted up a record, a Blue Oyster Cult record, and I think (prosecutor) John Fogleman said this was found in Damien's girlfriend's mother's house."
Critics of the case against the men argued that no direct evidence tied them to the murders, and that a knife recovered from a lake near the home of one of the men could not have caused the boys' wounds.
More recent DNA testing also demonstrated no links, according to the men's supporters, who included actors Johnny Depp and Winona Ryder and singers Eddie Vedder of Pearl Jam and Natalie Maines of the Dixie Chicks.
Echols said their support was "uplifting" and brought attention to their case, ultimately leading to their release.
Now, the men are having to get used to elements of modern life such as computers, the internet, and cell phones, things that most others take for granted. Even ordering a simple cup of coffee is different now.
"At one point, I went to a coffee shop and they were like, what kind of coffee do you want? And I'm like, kind of coffee?" Baldwin said.
The two have been out of prison for a month and a week. Baldwin says he now works for a construction company that's helping him get on his feet again, and he's learning how to drive.
Echols says he hasn't yet found a job but is interested in pursuing visual art. He got married while in prison to Lorri Davis, a woman who took up his cause and started writing him letters in prison.
She said they are still fighting for the real perpetrators to be brought to justice.
"We want to discover who did this," Davis said. "That's the most important thing."
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