In the week the Russia report rocked Westminster, raising questions about Russian influence on British politics,

we've been looking back at another explosive report on Russia, one that shook the world of sport.

I have to say that when the report came out in November of 2015. It basically proved that everything my wife and I were saying and that the

whistleblowing that we were doing had worked.

Vitali and Eulius Stepanov had been on the brink of divorce, but they were reunited when they joined

forces to blow the whistle on Russia's state-sponsored doping program. below the course, she goes to see the guy who masterminded the doping program.

And when she comes out of that meeting, she has hugely incriminating evidence.

Their revelations change the Olympics forever.

Having fled Russia in fear of their lives,

they've spoken to us whilst living in hiding.

You're listening to stories of our times from the Times and the Sunday Times.

I'm Manveen Rana. Today, the Russian doping scandal and the couple who risked their lives and marriage to blow the whistle. Tell us a bit about your history in this subject.

Oh my God, I think it goes back to the very beginning.

David Walsh is chief sports writer for the Sunday Times.

I was a young journalist who wanted to believe that all sports stars were heroes and I didn't want to write about my heroes being people who might cheat, that changed.

For decades, David has covered some of the biggest scandals in sporting history.

He led the pack in uncovering Lance Armstrong's doping program, and then another doping scandal

started to unravel.

At the Winter Olympics, Russia used to dominate the medal tables.

Until 2018, that is.

Russian athletes are competing under a neutral flag at the Winter Olympics this year.

Russia's official representation is banned at the Pion chain games because of a large-scale doping

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