In this two-part True Spies story, author and journalist Shaun Walker unmasks the greatest generation of Russian spies - the Great Illegals.

In Part Two, Shaun tells the story of Iosif Grigulevich - the Lithuanian Illegal who rose to the upper echelons of Italy's diplomatic community.

From SPYSCAPE, the home of secrets. A Cup And Nuzzle production. Series producer: Joe Foley. Produced by Frank Palmer.

Shaun Walker is the Central and Eastern Europe correspondent for The Guardian newspaper. He is the author of The Illegals: Russia's Most Audacious Spies and Their Century-Long Mission to Infiltrate the West.

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