More than one year after she was freed from a nine-month prison sentence in Russia, WNBA star Brittney Griner is opening up about her experience in the penal colony.

Griner, who wrote about her experience in the memoir "Coming Home" set to be released on May 7, shared some of the details with ABC's Robin Roberts in an interview that will air Wednesday night.

The two-time Olympic gold medalist and a nine-time WNBA All-Star was detained on Feb. 17, 2022, at Sheremetyevo International Airport in Khimki, Russia, after authorities said she had vape cartridges containing cannabis oil in her luggage – which is illegal in the country. Griner admitted she had the canisters in her luggage and accidentally packed them when she plead guilty to the charges in July 2022. She was sentence to nine years in prison.

Griner was transferred to the isolated IK-2 penal colony in Mordovia, more than 300 miles outside of Moscow, to serve her sentence. She described the poor conditions inside the prison.

"The mattress had a huge blood stain on it and they give you these thin two sheets, so you're basically laying on bars," Griner said.

The Phoenix Mercury star added the prisoners were only allowed one toilet paper roll a month and were given toothpaste that had expired 15 years prior. The conditions were frigid inside as well, and it not only took a toll on Griner's health, but she had to cut her dreadlocks because of it.

"It just had to happen," she said. "We had spiders above my bed, making a nest. My dreads started to freeze. They would just stay wet and cold and I was getting sick. You got to do what you got to do to survive."

The conditions in the penal colony have been described as brutal, and prisoners are required to work. Griner said she was ordered to cut fabric for military uniforms.

"It's a work camp. You go there to work. There's no rest," she said.

Brittney Griner says she made 'a mental lapse'

Griner detailed the moments leading up to and during her arrest at the airport. She said she packed all of her stuff, and when officials found the cartridges, she realized she made a mistake.

"I'm just like, 'Oh my God. How did I make this mistake? How was I this absent-minded?' I could just visualize everything I worked so hard for, it just crumbling and going away."

She compared it to a simple mistake like forgetting car keys in a car or losing your phone only to realize it was in your pocket. Griner recognized her mistake was on a bigger scale, "but it doesn't take away from how that can happen."

"It's just so easy to have a mental lapse," Griner said.

The U.S. government determined Griner had been "wrongfully detained" a few months into her sentence, and she was released on Dec. 8, 2022, after the U.S. agreed to a prisoner swap for convicted Russian arms dealer Viktor Bout.​​