Paris When It Sizzles (1964)

Richard Benson, an American screenwriter, has been hired by a producer to write a film. However, Benson has been neglecting his writing duties. With just two days before the producer arrives expecting a finished script, Benson hires Gabrielle Simpson, a spirited secretary, to help him pull together a story. As they brainstorm, they imagine themselves in the plot, crafting an espionage caper that blurs the line between fiction and reality.