The action takes place in 1900. After a high-profile trial on espionage activities, France is divided into two camps - anti-Semites and nationalists. A body of an unknown woman is pulled out of the river in Paris. A young and promising detective takes on the case. Unexpectedly, he uncovers a secret of national importance. A ruthless murder becomes the key to unraveling the most far-reaching conspiracies that marked the beginning of the century.