Robbe-Grillet's Trans-Europ-Express is a film-within-a-film, a kind of spoof spy film with sado-masochistic elements, or rather a comedy that doesn't really go very far but winds itself into repetitive circles, starts all over again, and then ends with a bang: but a quieter bang than at the beginning.
There's a film director, a producer and a continuation secretary working on the plot of a film, to be called 'Trans-Europ-Express', in a carriage on the Trans-Europ-Express. It's to be about a drug dealer called Elias, and as they create the story we see it played out by Elias (Jean-Louis Trintignant), who changes suitcases with another man after giving the password 'Père Petitjean', and he will use these magic words a number of times between the Gare du Nord and Antwerp, the town of his destination. In Antwerp he passes a row of houses, all with a prostitute in the window, although when one, Eva (Marie-France Pisier), comes up to him, he tells her that he only likes 'rape', and she agrees for extra money. After various escapades he learns that the whole business was only a dummy run to test his aptitude, and that the 'drugs' were in fact only powdered sugar.
So Elias is sent on a second journey, although when he meets Eva again he discovers that she is a police informant. He ties her up and strangles her, goes to a night club where he sees a woman stripping, is surrounded by the police and shot dead in the back yard. The three on the train think that diamond smuggling may have been a better idea for the film.