Warning: This article contains major spoilers from tonight's episode of "The Americans," "Chloramphenicol."

Ever since her first appearance in season 1 of "The Americans," Annet Mahendru has captivated audiences as Nina Sergeevna Krilova, a KGB underling whose knack for double-crossing the Soviet Union, the United States and back again has made her one of the most enigmatic characters on the series.

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