MARY LOUISE KELLY, HOST:
George Blake was a man of many, many identities - a British spy and MI6 officer turned double agent for Russia's KGB. On Saturday, when the Kremlin confirmed his death at the age of 98, George Blake had been living in Russia for more than half a century as Colonel Georgiy Ivanovich Bleyk.
STEVE VOGEL: His name, particularly in Great Britain, just generates huge rage.
AILSA CHANG, HOST:
That is Steve Vogel. He wrote about Blake in his book "Betrayal In Berlin." The anger towards Blake is a result of...
VOGEL: The damage that he did - and many people who were trying to help the West died because of his betrayals.
CHANG: Born in the Netherlands, George Blake evacuated to Britain during World War II. He soon joined British intelligence and was working in South Korea in 1950 when North Korea invaded. He was captured along with other Westerners. As a prisoner, Blake was already harboring communist sympathies, so he made a decision.
VOGEL: By his story, he approaches North Korean guards and says he wants to make contact with a Soviet representative.
KELLY: When Blake is eventually released, Britain welcomes him back as a hero. He rises in the ranks of British intelligence and begins his double life.
VOGEL: He becomes one of the very few that knows anything about this remarkable spy operation called the Berlin Tunnel, which is this effort to tap Red Army communications in East Berlin.
KELLY: Armed with that information, Soviet intelligence still lets the tunnel operate for a year. They value Blake so much, they fear his exposure more than they fear a breach of their secrets.
VOGEL: Once Blake is assigned to Berlin, he becomes more or less a one-man tunnel himself. And he has access to everything that the British station in Berlin was doing, which is a lot. And he passes on to the Soviets the names of its agents.
CHANG: Blake was eventually caught and sent to prison. In 1966, he escaped with the help of accomplices and a rope ladder thrown over a wall.
VOGEL: They managed, at the right moment, for Blake to scamper up the ladder, jump over the wall, land on the ground on the other side and he's thrown into the car. And they drive off with the most notorious spy, you know, in the world at that point.
KELLY: George Blake made it to the Soviet Union, which he found to be a disappointing version of the communism he believed in, according to Steve Vogel. Blake lived out his years in Russia, where he died a national hero. Transcript provided by NPR, Copyright NPR.