David Tennant cast as Alexander Litvinenko in new ITV drama

The drama will also look at Alexander's widow Marina (played by The Deuce's Margarita Levieva), who "fought tirelessly to persuade the British Government to publicly name her husband's killers and acknowledge the role of the Russian State in his murder".

Joining Tennant and Levieva in the cast are Catastrophe's Mark Bonnar and Small Axe's Neil Maskell, who play Scotland Yard officers Clive Timmons and Brent Hyatt respectively.

In a statement, writer Kay said: "In late 2006, Alexander Litvinenko was a living witness to his own murder. He spent his dying days entrusting the Metropolitan Police with the details of what happened to him.

"It took those police and his remarkable widow Marina Litvinenko a decade to have those claims ratified. Their stamina, hard work and bravery are what make this not only an essential story of our times but a privilege to be asked to write."

Litvinenko, a British-naturalised Russian who specialised in tacking organised crime, died in November 2006 after being poisoned with polonium-210, with police suspecting former Russian Federal Protective Service officer Andrey Lugovoy and Dmitry Kovtun as the killers.

Litvinenko will dramatise the Metropolitan Police's investigation, which began when two officers were called to London's University College Hospital to interview an rapidly deteriorating Litvinenko, whose information would help detectives track down the two Russians responsible for his poisoning.

While you’re waiting to watch Litvinenko, take a look at our other Drama coverage, or check out our TV Guide to find out what’s on TV tonight.