David Tennant: "Intense" Litvinenko was "a story that had to be told"

"I remember being appalled and bewildered and shocked and confused by the news story, like the rest of the world was," he said. "And then to read the way that George [Kay] had written the script and told the story was captivating and compelling."

He added that it was crucial to get the blessing of Litvinenko's surviving family, and explained how meeting his widow Marina opened his eyes to just how vitally important it was to approach the series in the right way.

"It's a story that has repercussions every day that we live through, you're very aware of that," he added. "Once you meet Marina, you feel you're not only carrying the importance of this story as a fable for our times, as a signifier for things that the world needs to be alerted to, you're also carrying the story of a family and the story of a couple and that felt very precious and very delicate.

"It’s something that we were all acutely aware of the whole time… it means so much to us Marina and [Alexander’s son] Anatoly give us their blessing, That’s the one thing we've all craved, because this is a hugely important story for the world, [but] it's also the story of a family and that’s something that was with us every minute on set."

Tennant also explained how filming the interviews that Litvinenko carried out from his hospital bed was "very intense".

"Jim [Field Smith, director] helped us by giving us space and allowing us to inhabit that moment, as much as you ever can," he said. "A film set by its very nature is an artificial construct, but you do all you can to try and get past that.

"When I was in the bed, I tended to stay in the bed, and the crew were very respectful about sort of being… not at a distance, very much connected to the action, but being very respectful of the sorts of processes everyone needed to go through, because it did feel very intimate."

‌Additional reporting by Morgan Jeffery.

Litvinenko arrives on ITVX as a full boxset on Thursday 15th December.

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