Putin, secret talks and the 'Merchant of Death': US basketball star Brittney Griner's long road to freedom from a Russian penal colony 

When US basketball star Brittney Griner was taken from a Russian penal colony and flown to Abu Dhabi, America's chief hostage negotiator was waiting for her on the tarmac. 

Roger Carstens wanted to be there in person to confirm to Griner what she had been told by her Russian captors, but perhaps could not yet believe.

Her nine-month-long nightmare was over.

He was taking her home. 

The 32-year-old sportswoman had become embroiled in a tussle between the United States and Vladimir Putin right at the moment the Russian strongman was isolated and increasingly desperate for leverage. 

Her dramatic arrest at Sheremetyevo International Airport in February kicked off months of secret negotiations between two nations that were barely on speaking terms. 

In the end, the United States was able to cut a deal with the Kremlin for Griner's release. 

But it would have to make sacrifices for her freedom. 

America's hostage envoy did not go to Abu Dhabi alone.

He brought with him a notorious Russian arms dealer nicknamed the "Merchant of Death" who had been in a US prison for 10 years. 

To get Griner out of Russia, the US had agreed to give up Viktor Bout, a man who had conspired to kill Americans, acquire and export anti-aircraft missiles, and provide support to a terrorist organisation.

And despite America's best efforts to strike a two-for-one deal, they had to leave behind another US citizen who has been languishing in a Russian prison for four years on espionage charges. 

The day Brittney Griner's nightmare began 

In February this year, Griner travelled to Moscow to play for a Russian women's basketball team, as she did almost every off-season. 

Despite being a world-class athlete and one of the best players in the Women's National Basketball Association (WNBA), she was paid $US221,450 ($326,613) a year.

This is, of course, a great salary for the average American. 

But a male baller playing for the NBA was easily earning Griner's yearly salary in a single game. 

For years, Russia had been luring the world's best female players to join their teams in the off-season with seven-figure salaries. 

And so, Griner went to Moscow to play for UMMC Ekaterinburg as she did every February for an easy $US1 million. 

But she made one catastrophic error. 

Griner forgot that she had a couple of cannabis oil cartridges in her luggage. 

While possessing the cartridges is legal in vast swathes of America, in Russia, it is enough to land you in prison for nine years.