The film began as a commission by Jean-Paul Belmondo to the screenwriter Jorge Semprún to develop a scenario about Stavisky. Resnais, who had previously worked with Semprún on La Guerre est finie, expressed his interest in the project (after a gap of six years since his previous film); he recalled seeing as a child the waxwork figure of Stavisky in the Musée Grevin, and immediately saw the potential of Belmondo to portray him as a mysterious, charming and elegant fraudster.

Semprún described the film as "a fable upon the life of bourgeois society in its corruption, on the collaboration of money and power, of the police and crime, a fable in which Alexander's craziness, his cynicism, act as catalysts".

Resnais said: "What attracted me to the character of Alexandre was his connection to the theatre, to show-business in general. Stavisky seemed to me like an incredible actor, the hero of a serial novel. He had the gift of bringing reality to his fantasies by means of regal gestures."  (Among many theatrical references, the film features a scene in the theatre in which Alexandre rehearses a scene from Giraudoux's Intermezzo, and another in which he attends a performance of Coriolanus. His office is adorned with theatrical posters.)

Source : Wikipedia.