In a constant blend of reality and fiction, a spy novel writer, François Merlin, leads a rather monotonous and uneventful life in Paris. However, his imagination is boundless, and his stories are filled with action and romance. When he's not writing, François faces a dull and gray world, until his muse appears in the form of Christine, a young and charming neighbor who becomes intrigued by him. His life takes an unexpected turn when the boundaries between his imaginary world and the real one begin to blur.
As François develops the plots of his books, he projects himself as a daring hero, the secret agent Bob Saint-Clair, in a universe teeming with danger, betrayal, and, of course, a bit of love. Every time François faces a challenge, the viewer is transported into his mind, where the action scenes are spectacular, and the beautiful women are as seductive as they are dangerous.
Tension escalates when a group of villains threatens to ruin both his life and Christine's, and François must learn to distinguish between his fantasy life and reality. With a blend of comedy, action, and romance, this film offers a fun look at the intrigues of creativity and the desire to escape from routine, while exploring a man's struggle to find his true place, both in his narrative and in love.