When WNBA star Brittney Griner finally boarded the plane last week that would take her back to the United States — after being detained in Russia since February on charges of marijuana possession — the U.S. officials with her thought she would want some peace and quiet in light of her ordeal.

“Brittney, you must have been through a lot over the last 10 months,” Roger Carstens, special presidential envoy for hostage affairs, told her, he said Sunday on CNN’s “State of the Union.”

“Here’s your seat,” he added. “Please feel free to decompress. We will give you your space.”

But to his surprise, Griner told him she just wanted to talk.

“Oh, no, I have been in prison for 10 months now listening to Russian,” he recalled her saying.

Carstens said Griner then moved past him and approached every crew member on the flight, “looked them in the eyes, shook their hands and asked about them, got their names, making a personal connection with them.”

He said they ended up talking for about 12 hours out of the 18-hour flight from the United Arab Emirates, where she was exchanged for convicted Russian arms dealer Viktor Bout.

“We talked about everything under the sun,” Carstens said. “I was left with the impression that this is an intelligent, passionate, compassionate, humble, interesting person, a patriotic person, but, above all, authentic.”

Carstens’ account included some new details about Griner’s journey back to the United States after she was released from Russian captivity. Griner was detained at a Moscow airport in February, just days before Russian President Vladimir Putin ordered troops to invade Ukraine.

She was sentenced to 9½ years in prison on drug-smuggling charges for bringing in vape cartridges containing a small amount of cannabis oil, which is illegal in Russia. Her lawyers said it was prescribed to treat chronic pain and other conditions.

Her sentence was close to the maximum for the offense under Russian law, and immediately slammed by the U.S. Embassy in Moscow as “a miscarriage of justice.” In early July, Griner wrote a letter to Biden to implore him to continue working for her and others’ release.

“As I sit here in a Russian prison, alone with my thoughts and without the protection of my wife, family, friends, Olympic jersey, or any accomplishments, I’m terrified I might be here forever,” Griner wrote in an excerpt of the letter shared by the talent agency representing the Phoenix Mercury center. “I realize you are dealing with so much, but please don’t forget about me and the other American Detainees.”

Maria Blagovolina, one of Griner’s Russian lawyers, told ESPN last week that the 6-foot-9 Griner spent most of her work hours in a Russian prison moving around bolts of fabric rather than sewing uniforms, as most of the other female prisoners did, because she was too tall for the sewing tables. She also was recovering from the flu. Griner recently cut off most of her hair, since washing it in the winter left her cold, Blagovolina said.

Griner landed in San Antonio on Friday and has been undergoing evaluations of her physical and mental health at a medical center on the Fort Sam Houston military base.

“Initial reports are she’s in very good spirits and in good health,” National Security Council spokesman John Kirby said on ABC’s “This Week.”

Griner’s return has prompted celebrations and praise, as well as criticism of President Biden and his administration over the swap.

“I think people of good faith can, in good faith, ask questions and be concerned about it, even when we’re very, very happy that Brittney Griner is back in the U.S.,” Preet Bharara, former U.S. attorney for the Southern District of New York, said on CNN’s “State of the Union.”

Bharara, a Democrat, was the prosecutor who oversaw the prosecution and conviction of Bout.

Bout is “someone who was convicted at trial by unanimous jury of conspiracy to kill Americans,” Bharara said. “He was convicted of conspiracy to provide material support to terrorists.”

But Bharara said he was giving the Biden administration the benefit of the doubt on the decision to exchange Bout. “He was a dangerous man then. I don’t know how dangerous he is now,” he said.

Rep. Adam B. Schiff (D-Calif.) said on he is “thrilled” Griner was home but was concerned the trade would serve as an incentive to “other despots to essentially grab an American and use them as a bargaining chip.” He also worried how Putin may leverage future detentions of U.S. citizens.

“He gets an arms dealer back. He also knows he can just roil the American body politic by picking one [American prisoner] to send back to the United States and leaving others in custody in Russia,” Schiff said.

Griner’s release also raised frustrations over the fact that Paul Whelan, a former Marine who was sentenced to 16 years in a Russian prison in 2020 after being convicted of spying, was not also included in the prisoner swap.

In July, the United States made a “substantial proposal” to Russia to secure the release of both Griner and Whelan together, but no agreement was reached then. The White House has said last week’s deal was not a question of “which American” to bring home, but rather one of whether to free Griner or no American at all.

Carstens said Sunday the United States remains focused on bringing Whelan home. He said that he spoke to the former Marine on Friday, telling him, “Keep the faith. We’re coming to get you.” Carstens declined to speak in detail about the ongoing negotiations with Russia for Whelan’s release.

“Even as we’re welcoming someone home, we still have work to do,” Carstens said. “So, as I’m shaking Brittney’s hands and we’re taking to the aircraft and having this great conversation, my brain is already thinking about Paul Whelan. What can we do to get him back? What’s our next move? What’s the strategy? How can we adapt?”

On Thursday, former national security adviser John Bolton told CBS News that the Trump administration, in which he served, had had the opportunity to swap Bout for Whelan, but was not interested. Bolton slammed the Griner-Bout exchange as “not a swap” but a “surrender.”

“Terrorists and rogue states all around the world will take note of this, and it endangers other Americans in the future who can be grabbed and used as bargaining chips by people who don’t have the same morals and scruples that we do,” Bolton said then.

Fiona Hill, the former Russia specialist for the National Security Council who worked in the Trump administration, confirmed that there were multiple efforts by Russia to secure Bout’s release in exchange for Whelan’s.

“President Trump wasn’t especially interested in engaging in that swap,” Hill said on CBS’s “Face the Nation.” “He was not particularly interested in Paul’s case in the way that one would have thought he would be.”

Mary Ilyushina, Tim Starks and Lauren Kaori Gurley contributed to this report.