The Little Murders of Agatha Christie

The Man in the Brown Suit (2x17)

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With the Cold War in full swing, Detective Laurence gets caught up in an affair of espionage with the Soviet Union. The Russian ballets that perform at the Lille opera house harbor spies in their midst, and top secret microfilms have gone missing. To help the French secret services, Laurence agrees to disguise himself as a woman to replace the opera secretary who's been murdered. Marlene sets out to teach "Brigitte" the secrets of femininity, which is no small task. Avril, however, finds this Brigitte particularly unlikeable. And on top of that, hasn't she seen her somewhere before?