Parisian detective Henri Cassin, exhausted and in need of a break, travels to a small French village for a restful holiday. While there, he becomes enchanted by the innkeeper's charming daughter, Nanette. Despite her engagement to a local farmer, Nanette falls for Cassin, stirring up resentment and jealousy within the tight-knit community. Tensions escalate when Nanette vanishes under mysterious circumstances shortly after Cassin proposes marriage.

Cassin takes it upon himself to uncover the truth behind her disappearance, employing his investigative skills amidst growing unease among the villagers. As clues begin to surface, a string of enigmatic events propels Cassin deeper into the dark heart of the village's secrets. What starts as a tranquil respite turns into a labyrinth of deceit, testing Cassin's resolve and pushing him to the brink as he navigates an intricate web of suspicions and hidden motives.