The courage of Marina Litvinenko is the driving force behind the ongoing fight to bring her husband’s killers to justice.
When the couple married in 1994 neither of them could have ever imagined the persecution and tragedy that lay ahead.
At that time Alexander was a senior figure in the FSB, the KGB’s successor, responsible for investigating terrorism and gang crime.
Marina, a graduate of the Moscow Oil and Gas Academy, was a qualified planning engineer but chose to teach choreography instead.
They met at her 31st birthday party and Marina would joke with friends that her tall, handsome boyfriend was a “birthday present”.
However, that year a decision to join an investigation into a plot to kill an entrepreneur would set the Government agent on a course to his death.
The entrepreneur was Boris Berezovsky and within six years the family, now with a young son, would be forced to flee Russia.
After several years those investigating the plot were themselves allegedly ordered to kill Berezovsky because he was a political embarrassment.
In November 1998, Alexander sealed his fate by going public with extraordinary claims of a State-sponsored murder plot.
Images of the press conference, where some of the participants wore masks to hide their faces, were broadcast across Russia.
The scandal led to the resignation of the FSB director and Vladimir Putin, future Russian president, took his place.
Alexander was sacked and arrested and over the next two years attempts were made to put him on trial twice on charges of exceeding his official powers.
Eventually Alexander was released on bail and the family fled to the UK, via Turkey, to claim asylum.
Today, Marina has Putin firmly in her sights as a key player behind the appalling murder of her husband.
She remains under police protection with her young son Anatoly and in close contact with Berezovsky, now also in exile in London.
They are both founding members of the Litvinenko Justice Foundation which is lobbying the UK Government to pressure the Russians.
In an emotional open letter written to Putin earlier this year, she urged him to co-operate with the British inquiry.
She told the Russian President that if he had noting to hide he would welcome a thorough investigation.
She said: “If you and the Russian state are not responsible for the murder, surely you should be doing everything possible to assist the British authorities in discovering who is guilty?
“I can assure you I will not rest until the murderers are brought to justice.”