Reilly: Ace of Spies

An Affair with a Married Woman (1x1)

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Sigmund Rosenblum is on a mission in Russia. His train is stopped and he is arrested, but he escapes and travels to London. There, he compromises Margaret Thomas, the young wife of a rich clergyman. Her husband dies, Rosenblum marries her, takes her maiden name (becoming Sidney Reilly) and is posted to the Far East.