Yulia Navalnaya, wife of Alexei Navalny, on continuing the fight against Putin

(CBS, KYMA/KECY) - The death of Alexei Navalny in a Russian prison in the Arctic this February sparked an outcry around the world. He was compared to Nelson Mandela as a prisoner of conscience.

While behind bars, he completed a memoir, documenting his three-year battle to survive the unspeakable prison conditions.

This is CBS' third story on Navalny. The first in 2017 when he stood up to Vladimir Putin by running against him for president of Russia. When he was arrested in 2021, Navalny's popularity as the most prominent leader of the Putin opposition was growing.

He was defiant, brave for taking on the all-powerful Vladimir Putin out in the open, denouncing him as a gangster. He refused to back down and paid the ultimate price: Three years in Russian prisons and then this year, death at age 47.

His wife Yulia Navalnaya, once her husband's silent partner, is now the leader of his opposition movement.

During an interview with Lesley Stahl on 60 Minutes, she says Alexei's memoir, "Patriot," represents his final act of defiance.

"It was his life. It was his every-minute job to fight with Putin's regime," Navalnaya expressed.

To watch the full interview, click here.