The victim is Sophie Monterant: a young actress who is already challenging the divine Sarah Bernhardt for the finest roles. Inspector Gautier visits the theatre to see Sophie at the first night of Dame aux Camélias, but the first night is also to be her last: after the curtain fall, Sophie eats a poisoned chocolate and dies.

Gautier is immediately on the case and his investigation takes him to the upper echelons of Parisian society, including the blue-blooded Comte de Limousin and the Minister for the Beax-arts, who is likely to become the next president of France. Gautier's impertinence enrages Courtrand, the director of the Sûreté, but what is Courtrand himself concealing?