Paris Police 1900

President Félix Faure has just died in the arms of his mistress, Marguerite Steinheil. With the Republic on the verge of explosion, Prefect Lépine is called back to business.

The courtesan Meg, who became a spy on behalf of Puybaraud, head of the police and sworn enemy of the Prefect, infiltrates the Guérins.

Inspector Jouin is in love with Jeanne, a young lawyer who cannot practice but works with Maître Weidmann in the Jewish quarter. She decides to help him with the Berger case.

A few days before the opening of the Dreyfus trial, tension is mounting in the streets of Paris. Lépine foils to his advantage the trap of personal scandal set for his wife.

Meg has fallen under the spell of Gabriel Sabran, as more and more evidence appears against him in the investigation into Josephine's murder.

Exhausted by years of enslavement and sickened by the Berger affair, Fiersi distances himself from Puybaraud as Jules Guérin takes refuge in rue Chabrol.