Tennant will portray the late Russian spy in the drama series, Litvinenko, about the death of Litvinenko in 2006.
His death came 22 days after being poisoned with a rare and difficult-to-detect radioactive substance, Polonium-210, at a London hotel.
Prior to his death, he gave interviews to the police from his hospital bed, containing information that would ultimately lead investigators to the people responsible for his poisoning.
Created by George Kay, Litvinenko will tell the story of his widow, Marina (Margarita Levieva), and her battle to convince the British government to publicly name her husband’s killers and acknowledge the Russian State’s role in his murder.
The first image released by ITV shows Tennant as the spy in a hospital bed, with no hair and a gaunt appearance.
It is a nearly exact replica of a photo of Litvinenko released to the press in 2006.
When the programme was announced in 2021, Kay spoke out about bringing the story to life, and confirmed that it was being made with the co-operation and support of “key individuals” connected to the investigation.
“In late 2006, Alexander Litvinenko was a living witness to his own murder,” Kay said in a statement.
“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.”
Along with Tennant and Levieva, Litvinenko will also star Catastrophe’s Mark Bonnar and Kill List actor Neil Maskell.
Litvinenko will launch on ITV’s streaming platform, ITVX, on Thursday 15 December.