In ‘Litvinenko,’ a Russian Whistle-Blower Investigates His Own Murder

LONDON — In the middle of AMC+’s new dramatization of the poisoning of the intelligence agent Alexander V. Litvinenko, a police officer asks a pathologist about the state of the man’s organs when he died. The doctor thinks for a moment, as though considering how graphic to be, and then replies, “Sludge.”

It’s a visceral moment in “Litvinenko,” a limited series written by the “Lupin” creator George Kay that depicts Litvinenko’s 2006 poisoning in London via a cup of tea laced with the radioactive element polonium 210, and its aftermath.

While many viewers will remember the photo of Litvinenko on his deathbed, gaunt and newly bald, that appeared on front pages around the world, fewer will know the details of his final days, and how — convinced he was poisoned by President Vladimir V. Putin of Russia — he aided the investigation into the attack, even as his internal organs were failing.

The story of a former K.G.B. agent assassinated in broad daylight in the dining room of a British hotel could have made for a sensationalized show about international intrigue. But “Litvinenko,” which comes to AMC+ and Sundance Now on Friday, instead focuses on the human cost behind the headlines.