How to watch the documentary Litvinenko was based on

However, just which documentary was that, how can you watch it and what other documentaries have focused on the Litvinenko case?

Read on for everything you need to know about the documentary Litvinenko was based on.

Which documentary was Litvinenko based on?

Speaking exclusively with RadioTimes.com, the series' writer George Kay revealed that the starting point for the new ITVX drama was a 2017 documentary called Hunting the KGB Killers, directed by Chris Malone, produced by Richard Kerbaj and narrated by actor Eddie Marsan.

Kay said: "There's a documentary-maker called Richard Kerbaj who is a co-producer on the drama and he had made a film about Litvinenko's case, but told it from a police perspective.

"There's been various books and accounts of it but his was definitely from the police perspective, but also included interviews with Marina and with Anatoly and the family and it was very moving.

"But it was also a real great puzzle in terms of the story he told, of how the police tried to get their heads around what on earth had happened. From the disbelief of the initial claims made, correct claims, but seemingly outlandish claims made by Sasha Litvinenko, to just try to work out what polonium was, and what risk it presented to the British public.

"But also then, at a higher level, other reasons why obfuscation might happen or it might become increasingly difficult to get justice for Marina and for Sasha, for the family as the years went on. And the government's changed, its relationship with Russia changed and so on.

"So it was sort of a multi-tiered thing, which felt really ripe for adaptation and a really great way in."

Kay went on to say that the documentary "was really attractive as an adaptation and as a retelling of that version of the story. But of course, it isn't just an adaptation of a documentary.

"I then went to meet Marina and Anatoly and the police involved and we had long conversations about how they went about solving this. Everyone you see in the drama is a real person, bar the odd composite character based on research and they've all been very supportive of it."

How can you watch Hunting the KGB Killers?

Hunting the KGB Killers first aired on Channel 4 in the UK in 2017, but is no longer available to watch on the broadcaster's online platform.

However, you can now watch the full hour-long documentary for free on YouTube, on the channel Real Stories. You can find the documentary here.

What other documentaries have been made on the Litvinenko case?

Alongside the four-part drama series, ITVX has also produced a one-hour documentary film, entitled Litvinenko: The Mayfair Poisonings, which is also available now.

According to the film's synopsis, it details "the events surrounding the assassination of Russian national Alexander Litvinenko in 2006", saying that it sees the people who were actually there tell the "real story of not just a murder inquiry, but also a radiation health emergency that shocked the world".

The synopsis continues: "Alexander Litvinenko died over 15 years ago, yet his poisoning is still one of the most prominent assassinations in history.

"For the first time ever, this documentary will reveal the previously untold story of the experts behind-the-scenes who dealt with the deadly radioactive poisoning on British soil and those who led the investigation into Litvinenko’s murder. The documentary provides a unique, alternative view of Alexander’s assassination, with an interview with his wife, Marina Litvinenko.

"In her first major documentary interview since the European Court of Human Rights ruled that there was outside involvement in Alexander’s assassination, Marina tells her side of the story; how difficult it was having her world turned upside down, only having 15 minutes to leave her house with her young son due to fears of radiation contamination, and about that world-renowned interview given from Alexander’s hospital bed."

Read more:

• Litvinenko star says David Tennant is “remarkable” in ITVX drama
• Litvinenko director: Nailing David Tennant's Russian accent was "tricky"
• Litvinenko is a "feat of acting" from David Tennant, says Neil Maskell
• David Tennant explains how he transformed into Litvinenko for drama

Both Litvinenko and Litvinenko: The Mayfair Poisoning are available on ITVX now.

For more news, interviews and features, visit our Drama hub, or find something to watch now with our TV Guide and Streaming Guide.

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