Brittney Griner reflects on moment she was detained in Russia in exclusive '20/20' special

WNBA star Brittney Griner, who was released from Russian detention in a prisoner swap in December 2022, opened up for the first time about her harrowing experience in a Russian prison in an exclusive interview that will air May 1 on a special edition of "20/20." "Good Morning America" will have a first look earlier that day.

Griner, 33, a two-time Olympic gold medalist and a nine-time WNBA All-Star who plays for the Phoenix Mercury, reflected on the "mental lapse" that led to her months-long detention in Russia when vape cartridges containing cannabis oil -- an illegal substance in the country -- were found in her luggage.

"I could just visualize everything I worked so hard for just crumbling and going away," Griner told Roberts. "And then to be somewhere where there's no understanding."

Griner was returning to Russia to play during the WNBA's off-season when she was detained on Feb. 17, 2022, at Sheremetyevo International Airport in Khimki after the cartridges were found.

"You know there are those who say, 'Come on. How did you not know that you had cartridges in your in your luggage?'" Roberts asked.

"Have you ever forgot your keys in your car? Left your car running? Have you ever-- you know, where's my glasses? They're on top of your head. Where's my phone? Oh, it's in my pocket. It's just so easy to have a mental lapse," Griner said.

"Granted, my mental lapse was on a more grand scale. But it doesn't take away from how that can happen," she added.

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Griner pleaded guilty to drug charges on July 7, 2022, saying that the vape cartridges containing hashish oil were in her luggage unintentionally. She testified that she had "no intention" of breaking Russian law and packed the cartridges by accident.

"This was a mistake. It was an accident, which I understand accidents have repercussions," Griner told Roberts. "And I'm American in Russia where relations aren't the best. You know?"

Russia's invasion of Ukraine began one week after Griner was detained on Feb. 17, 2022 - a war that intensified Russian tensions with the U.S. Some American officials also expressed concern that Americans jailed in Russia could be used as leverage in the ongoing conflict.

The Houston native said that when she realized that the cartridges were in her bag, she thought of her family.

"I'm thinking about my wife. I'm thinking about my dad. You know, what my mom's gonna think, what my family's gonna think, public opinion is gonna think. You know, I can just see the headlines now," she said.

Griner's family, including her wife Cherelle Griner, were outspoken advocates for her release and continuously called on the Biden White House to intervene and bring her home.

Brittney Griner reflects on gut-wrenching moment she was detained in Russia

The U.S. State Department classified Griner's case as "wrongfully detained" in May 2022 and the Biden administration worked for months to secure her freedom. During Griner's detention, top athletes in the WNBA and NBA brought attention to her case on and off the court, putting pressure on the Biden White House to secure her release.

She was sentenced to nine years in prison on Aug. 4, 2022, but amid mounting pressure on the White House to strike a deal and bring her home, the U.S. agreed to swap Griner for convicted Russian arms dealer Viktor Bout and she was released on Dec. 8, 2022 after nearly 10 months in prison.

Griner announced exclusively to "GMA" on Feb. 6 that she is set to release a new memoir on May 7 titled, "Coming Home" - a book that will detail her harrowing incarceration in Russia and subsequent release.

"'Coming Home' begins in a land where my roots developed and is the diary of my heartaches and regrets," Griner said in a statement. "But, ultimately, the book is also a story of how my family, my faith, and the support of millions who rallied for my rescue helped me endure a nightmare."

Griner's full exclusive interview will air May 1 on a special edition of "20/20."

ABC News' Eboni Griffin, Joseph Diaz, Gail Deutsch, Susan Welsh, Netsanet Negussie, Kaitlin Amoroso, Danielle Genet and Chris Donovan contributed to this report.

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